# The Last Train to Hoshikawa

## Long-Form Visual Novel Story Bible & Branching Scene Graph

**Genre:** Anime romance / supernatural mystery  
**Format:** Offline Android visual novel; persistent route unlocks, save/load, backlog  
**Rating target:** Teen / 12+ emotional suspense; no explicit sexual content  
**Playable-scene count:** **98** (`C001–C034`, `A001–A022`, `R001–R022`, `T001–T020`)  
**POV:** First-person past tense from Ren, with occasional clearly labeled memory fragments  
**Primary theme:** Loving someone means remembering them truthfully—not possessing a perfect version of them.  
**Secondary themes:** Grief versus erasure; evidence versus exploitation; choosing an imperfect future over a preserved past.

---

# 1. High Concept

At 22, **Ren Takamori** returns to the fading coastal town of Hoshikawa to close his late grandmother’s house. On his first night, a silver train arrives at a platform abandoned eight years earlier. Its destination board reads **HOSHIKAWA — 00:00**, its windows show stars instead of passengers, and its conductor calls Ren by a name he does not remember giving.

Ren soon discovers gaps in his adolescence and a recurring image: his older sister **Yui**, whom every official record insists never existed. Three women pull at different pieces of the mystery:

- **Aoi Mizuno**, a quiet astronomy student who hears the observatory’s dead radio whisper Ren’s forgotten promise.
- **Reina Kisaragi**, a sharp investigative journalism intern following evidence that her father vanished while exposing an illegal experiment.
- **Mio Senda**, the station attendant who knows the midnight train’s timetable and has spent eight years ensuring nobody boards it.

The abandoned Hoshikawa Observatory, the discontinued Platform Zero, and the town’s missing memories are parts of one machine. The impossible train is not a ghost in the ordinary sense. It is a moving archive of unresolved memories, circling the one night when a scientific disaster was hidden by making the town forget.

The common route establishes the rules and routes Ren toward either Aoi’s intimate, celestial understanding of memory or Reina’s courageous pursuit of public truth. Each romance route can end badly, bittersweetly, or well. Completing both good endings unlocks a persistent **True Route**, in which remembered possibilities become the final evidence needed to break the loop without erasing the people inside it.

---

# 2. Tone, Style, and Content Boundaries

## 2.1 Tone pillars

1. **Coastal melancholy:** Salt-stained signs, cicadas after rain, empty arcades, night trains heard beneath surf.
2. **Warm adult romance:** Shared work, honest disagreement, chosen vulnerability, restrained physical affection, earned confession.
3. **Fair-play mystery:** Every final revelation is foreshadowed by visible clues. Routes reinterpret clues rather than replacing canon.
4. **Hope through acceptance:** Good endings do not restore the dead. They restore history, agency, and the ability to grieve.
5. **Escalating unreality:** Begin with one impossible train; expand gradually to altered photographs, missing days, and overlapping timelines.

## 2.2 Romance boundaries

- Ren (22), Aoi (21), Reina (23), and Mio (24) are adults.
- Aoi and Reina are the only romance routes.
- Mio is a trusted mystery ally and never receives flirt choices, romantic CG framing, jealousy scenes, or an ending tease.
- Flashbacks depict Ren, Aoi, Reina, and Mio as adolescents only in family/mystery contexts; there is no romantic or sexual content in those scenes.
- Affection is conveyed through hand-holding, embraces, a kiss in each good route, emotional intimacy, and future plans. No sexual explicitness.
- The True Route requires an honest, exclusive choice between Aoi and Reina (or a non-romantic “walk alone” variant if desired by production); it is not a harem resolution.

---

# 3. Setting Bible

## 3.1 Hoshikawa

A fictional town on Japan’s eastern coast, built between sea cliffs and a narrow railway shelf. Once prosperous from observatory tourism and rail maintenance, it has declined since the **Hoshikawa Line Accident** eight years ago. The official explanation—an electrical fire during a storm—never accounted for five missing people or why town records from that night contain blank hours.

### Recurring locations

- **Hoshikawa Station:** Two active platforms and fenced-off **Platform Zero**, formerly serving the observatory spur. Mio works the late shift.
- **Platform Zero:** Appears longer from inside than outside. The impossible train arrives at 00:00 only when a strong unresolved memory acts as a “ticket.”
- **Hoshikawa Observatory:** Abandoned after the accident. Its main reflector contains the **Asterism Lens**, a meteor-glass resonator.
- **Takamori House:** Ren’s late grandmother’s house. Yui’s hidden cassette recorder and a scratched family height chart survive here.
- **Mizuno Cottage:** Aoi’s family home below the observatory road, filled with star maps and her father’s unopened study.
- **Kisaragi Press Annex:** Reina’s temporary office in a disused photo shop. Walls become a physical evidence board.
- **Seawall / Tide Shrine:** A quiet emotional refuge. The shrine bell rings when the train takes a memory.
- **Rail Tunnel 4:** The physical throat of the loop, connecting station wiring to the observatory grounding array.
- **Summer Star Festival:** The town’s annual attempt at normal life. Its lantern blackout masks the train’s strongest manifestation.

## 3.2 Supernatural-scientific rules

1. **The train preserves, it does not resurrect.** Passengers encountered aboard are memory-echoes with continuity and agency, but their biological originals died during the accident.
2. **A “ticket” is an unresolved memory.** Regret, promise, or suppressed truth allows boarding. Literal paper tickets only focus the connection.
3. **The train cannot create facts.** It can remix memories, simulate desired outcomes, and hide context, but every image originates in someone’s remembered experience.
4. **Removing a memory incurs debt.** The loop remains stable by siphoning related memories from witnesses. `memory_debt` tracks Ren’s losses.
5. **Names anchor identity.** Speaking a full name while holding an associated object helps an echo retain selfhood.
6. **Dawn forces departure.** Anyone still aboard at the first direct sunlight risks becoming an echo.
7. **The Asterism Lens and rail circuit are one system.** Observatory optics encode memory; the rail loop repeats it; Platform Zero provides access.
8. **The Mercy Protocol caused the town-wide amnesia.** It was activated to prevent the unstable Lens from following every witness home, but corporate tampering turned a one-time purge into an annual siphon.
9. **Truth alone is insufficient; consent matters.** Forcing an echo out or broadcasting private memories destabilizes the system. Good endings require allowing the trapped echoes to choose release.
10. **The True Route needs two complementary solutions.** Aoi’s route discovers how to separate identity from pain; Reina’s route discovers how to preserve evidence without exploiting private memory. Persistent completion of both provides `fragment_star` and `fragment_ink`.

---

# 4. Character Bible

## 4.1 Ren Takamori — protagonist, 22

**Occupation:** Recently left a Tokyo sound-engineering apprenticeship after his grandmother’s death; freelance audio restoration skills.  
**Surface:** Polite, observant, dryly funny, conflict-avoidant.  
**Wound:** He believes forgetting pain is a form of survival, but secretly interprets his missing memories as moral failure.  
**Hidden history:** At 14, Ren followed Yui into the observatory during the accident. He promised to carry her story out. The Mercy Protocol erased Yui from most records and Ren’s conscious memory.  
**Arc:** Passive recipient of loss → active investigator → person who can remember without being ruled by memory.  
**Romantic need:** Someone who challenges his instinct to disappear inside other people’s needs.

## 4.2 Aoi Mizuno — romance route, 21

**Occupation:** Third-year astronomy student home for summer; cataloguing the observatory archive before demolition.  
**Voice:** Quiet, precise, unexpectedly playful; uses celestial metaphors only when emotionally cornered.  
**Strength:** Deep patience and capacity to notice what others overlook.  
**Flaw:** Treats endurance as virtue and withholds needs until silence becomes a lie.  
**Wound:** Her father, Dr. Satoru Mizuno, vanished in the accident. Her mother taught her never to speak of it publicly. Aoi fears that seeking him means choosing the dead over the living.  
**Route question:** Can love make room for grief without becoming a shrine to it?  
**Romance milestones:** Shared meteor watch → mutual confession of fear → first hand-hold aboard train → disagreement over preserving echoes → kiss after choosing dawn.

## 4.3 Reina Kisaragi — romance route, 23

**Occupation:** Investigative journalism intern at the regional paper *Seito Daily*.  
**Voice:** Fast, incisive, teasing; asks direct questions and dislikes euphemism.  
**Strength:** Moral courage and ability to turn scattered facts into a public case.  
**Flaw:** Uses investigation to control vulnerability; risks treating people as sources before people.  
**Wound:** Her father Eiji, a railway safety investigator, vanished in the accident. His unfinished exposé became a family disgrace after the sponsor framed him for sabotage.  
**Route question:** Can truth be told without consuming the people who survived it?  
**Romance milestones:** Adversarial interview → partnership pact → darkroom vulnerability → conflict over publishing Ren’s memories → apology and informed consent → kiss after the presses roll.

## 4.4 Mio Senda — mystery ally, 24; not romanceable

**Occupation:** Night station attendant; unofficial caretaker of Platform Zero.  
**Voice:** Practical, understated, occasionally deadpan.  
**Strength:** Knows the railway’s physical systems and keeps calm during manifestations.  
**Flaw:** Hoards responsibility, believing secrecy is the only barrier protecting others.  
**Wound:** Her older brother Haru, the train’s junior conductor, died in the accident. Mio has spoken to his echo every year but never said goodbye.  
**Function:** Explains practical rules, enables route convergence, and models non-romantic love and grief. High `mio_trust` improves all good endings but never changes romance selection.

## 4.5 Yui Takamori — central missing person, 19 at death

Ren’s older sister and a university assistant on Project Polaris. Warm, stubborn, and technically gifted. She activated the Mercy Protocol, then stayed aboard the memory loop to keep Ren and the others from being overwritten. She is neither an omniscient ghost nor a secret villain. Her flaw was making a unilateral choice that took everyone’s memories “for their own good.” The True Route requires Ren to forgive her without endorsing that choice.

## 4.6 Satoru Mizuno — Aoi’s father, 42 at death

Observatory director and creator of the Asterism Lens. Intended it to preserve testimony from disaster victims, but accepted Kurogane Rail funding and underestimated the sponsor’s appetite for behavioral applications. He tried to shut Polaris down and died separating Aoi’s memory trace from the Lens.

## 4.7 Eiji Kisaragi — Reina’s father, 39 at death

Railway safety investigator. Discovered that Kurogane executive **Masato Kurobe** bypassed the Lens’s isolation relay for a live demonstration. Eiji brought evidence to the observatory and attempted to evacuate the spur train. The company later forged logs to blame him.

## 4.8 Haru Senda — Mio’s brother, 26 at death

Junior conductor of the observatory spur. He turned the train back toward Platform Zero to evacuate those at the observatory, inadvertently completing the resonant circuit. His final manual brake prevented the loop from spreading down the national line.

## 4.9 Masato Kurobe — human antagonist, 55 in present

Retired Kurogane Rail executive. He did not intend mass death but knowingly disabled safeguards and later ordered the cover-up. He appears only through recordings and a present-day attempt to seize the Lens. He is not aboard the train; therefore the protagonists cannot defeat the mystery by blaming an evil ghost.

---

# 5. Canonical Mystery Timeline (Author-Only Spoilers)

## Eight years ago: “The Missing Night”

1. Project Polaris prepares a meteor-shower demonstration of the Asterism Lens, designed to record emotionally vivid testimony as light interference.
2. Kurobe orders engineer logs altered and the isolation relay bypassed so the Lens can transmit through the old observatory rail power circuit.
3. Eiji Kisaragi arrives with proof and tells Satoru Mizuno to cancel. Yui helps copy the logs to magnetic tape because digital files are being remotely purged.
4. A coastal storm cuts normal power. Haru drives the spur train uphill to evacuate staff. The train closes the circuit between Platform Zero, Tunnel 4, and the Lens.
5. The Lens begins recording everyone nearby, including adolescents Ren, Aoi, Reina, and Mio, who are at separate festival locations connected by the town PA/rail grid.
6. Satoru manually fractures the optical feed. Eiji tries to disconnect the rail bus. Both die in the surge; Haru dies holding the train brake.
7. Yui activates the Mercy Protocol to push the adolescents’ active memories out of the Lens. It works only partially: their autobiographical links to the night—and most public traces of Yui—are stripped into the train.
8. Yui remains consciously coupled long enough to keep the loop local. She dies before dawn, but her echo becomes the train’s “conductor voice.”
9. Kurogane recovers physical bodies except Yui’s, steals core files, falsifies the electrical-fire report, and leaves the cracked meteor-glass core because it appears inert.
10. Every Star Festival since, the corrupted purge routine siphons small related memories from Hoshikawa residents to keep the loop coherent. Mio secretly blocks Platform Zero, limiting casualties.

## Present-day truth distribution

- **Common route:** Establishes train rules, Yui’s existence, and a link between station and observatory.
- **Aoi route:** Reveals the identity-separation method, Satoru’s culpability/remorse, and the emotional mechanism of the Mercy Protocol.
- **Reina route:** Reveals corporate tampering, Eiji’s innocence, the physical rail circuit, and ethical publication method.
- **True route:** Reveals Yui activated Mercy, Kurobe’s complete role, why Ren was selected as anchor, and how to release every echo while preserving consensual testimony.

---

# 6. State Model and Implementation Notes

## 6.1 Persistent variables

These survive ending/reset and belong in profile storage, not a single save slot.

| Variable | Type | Default | Purpose |
|---|---:|---:|---|
| `aoi_good_clear` | bool | false | Set by `A022`; unlock component |
| `reina_good_clear` | bool | false | Set by `R022`; unlock component |
| `fragment_star` | bool | false | Persistent insight from Aoi good ending |
| `fragment_ink` | bool | false | Persistent insight from Reina good ending |
| `true_route_unlocked` | derived bool | false | `aoi_good_clear && reina_good_clear` |
| `true_good_clear` | bool | false | Set by `T020` true-good variant |
| `ending_gallery` | set<string> | `{}` | Ending IDs seen |
| `clue_codex` | set<string> | `{}` | Optional persistent clue glossary; never used to bypass route logic |

## 6.2 Run-local variables

| Variable | Type / range | Default | Main sources |
|---|---|---:|---|
| `aoi_aff` | int 0–8 | 0 | Listening, honesty, shared stargazing, respecting choice |
| `reina_aff` | int 0–8 | 0 | Partnership, candor, consent, shared risk |
| `mio_trust` | int 0–5 | 0 | Obeying platform safety, including Mio, respecting Haru |
| `evidence` | int 0–8 | 0 | Physical documents, audio repair, relay photos, testimony |
| `memory_debt` | int 0–6 | 0 | Reckless boarding, trading memories, staying past dawn |
| `courage` | int 0–5 | 0 | Facing manifestations, speaking names, refusing ideal illusions |
| `privacy` | int -2–4 | 0 | Protecting consent and private testimony; negative means exploitative |
| `train_marks` | int 0–3 | 0 | Number of direct exposures; drives visual/audio distortions |
| `route_focus` | enum | none | `aoi`, `reina`, or `true` at lock |
| `promised_return` | bool | false | Aoi emotional callback |
| `press_pact` | bool | false | Reina partnership callback |
| `yui_named` | bool | false | Ren accepts Yui’s existence aloud |
| `haru_token` | bool | false | Mio side clue / ending support |
| `polaris_tape` | bool | false | Restored magnetic evidence |
| `relay_photo` | bool | false | Corporate tampering evidence |
| `identity_formula` | bool | false | Aoi route solution component |
| `consent_protocol` | bool | false | Reina route solution component |
| `aoi_truth` | bool | false | Told Aoi Ren’s full recovered memory before climax |
| `reina_truth` | bool | false | Told Reina full memory and negotiated publication scope |
| `echo_consent` | int 0–4 | 0 | True-route release consent collected |
| `true_partner` | enum | none | `aoi`, `reina`, or `alone` |

## 6.3 Route lock

At `C031`, route options are shown as follows:

- **Aoi route:** always visible if `aoi_aff >= 2`; highlighted if `aoi_aff > reina_aff`.
- **Reina route:** always visible if `reina_aff >= 2`; highlighted if `reina_aff > aoi_aff`.
- **Choice route selection:** if both qualify, player explicitly chooses; ties never silently decide romance.
- **Fallback:** if neither reaches 2, `C034` provides a non-ending recovery choice that adds one point based on whom Ren calls, then returns to `C031`.
- **True route:** visible only if persistent `true_route_unlocked == true`; choosing it resets route-specific run variables as listed in `T001` while preserving common-route rapport.

## 6.4 Threshold philosophy

Good endings require a combination of affection, investigation, courage, and ethical choices. Affection alone cannot solve the mystery; evidence alone cannot produce a romance ending. Bad endings come from identifiable player behavior rather than one opaque final choice.

---

# 7. Scene Object Schema

Each scene below maps cleanly to a JSON object:

```json
{
  "id": "C001",
  "title": "Salt on the Rails",
  "route": "common",
  "conditions": ["always"],
  "summary": "...",
  "choices": [
    {
      "label": "Follow the bell",
      "effects": {"courage": 1},
      "next": "C002"
    }
  ],
  "auto_next": null,
  "clues": ["clue_id"],
  "cg": null
}
```

**Implementation conventions**

- Conditions are evaluated before displaying the scene.
- Effects apply immediately when a choice is confirmed.
- A choice may point to the same next scene while altering later dialogue/availability.
- Ending scenes set persistent flags only after the final confirmation prompt, protecting against accidental unlocks from preview/gallery playback.
- Backlog stores resolved text, including variable substitutions, but never replays effects.
- Save/load stores scene ID, local variables, displayed choice IDs, music position if desired, and deterministic RNG seed. No mystery-critical choice uses randomness.

---

# 8. Common Route Scene Graph — 34 Scenes

## Act C-I: Return and First Arrival

### C001 — Salt on the Rails
- **Conditions:** `always`
- **Summary:** Ren arrives at dusk to settle his grandmother’s estate. The station clock skips from 23:57 to 23:59, and he hears a departure melody his childhood memory cannot place. Mio checks his ticket and goes still at his surname.
- **Choices:**
  - `C001_A` “Ask why my name surprised her.” → `mio_trust +1`; Mio admits she knew a Takamori girl but retracts it. → `C002`
  - `C001_B` “Let it pass and ask about the old platform.” → `evidence +1`; learn Platform Zero officially closed eight years ago. → `C002`
- **Clues:** `clue_clock_skip`, `clue_mio_knows_takamori`

### C002 — Grandmother’s Empty House
- **Conditions:** `always`
- **Summary:** In the salt-stiff house, Ren finds two teacup rings on a desk despite remembering living here alone each summer. A carved height chart has “REN” and a sanded-out taller name.
- **Choices:**
  - Photograph the height chart. → `evidence +1`; unlock close-up later. → `C003`
  - Touch the erased carving and try to remember. → `memory_debt +1`, `yui_named` remains false; hear “Yu—” in static. → `C003`
- **Clues:** `clue_erased_height_chart`

### C003 — The Train at Midnight
- **Conditions:** `always`
- **Summary:** A bell draws Ren back to Platform Zero. A silver three-car train arrives without disturbing rust on the tracks. Its windows contain a moving star field. A woman’s announcement says, “Ren, this is your last chance to remember.”
- **Choices:**
  - Step toward the open door. → `courage +1`, `train_marks +1`; Mio pulls him back. → `C004`
  - Call for Mio before moving. → `mio_trust +1`; she arrives with a red signal lantern. → `C004`
- **Clues:** `clue_train_knows_ren`, `clue_rust_undisturbed`
- **CG:** First impossible train reveal.

### C004 — Red Lantern Rule
- **Conditions:** `always`
- **Summary:** Mio locks the platform gate and states three rules: never board alone, never surrender a name, and leave before dawn. She refuses to explain how she knows. Ren notices a conductor’s whistle tied beneath her uniform.
- **Choices:**
  - Promise to follow her rules. → `mio_trust +1`; safer option later. → `C005`
  - Demand proof before promising. → `evidence +1`; Mio shows an eight-year-old ticket stamped tomorrow’s date. → `C005`
- **Clues:** `clue_three_rules`, `clue_haru_whistle`

### C005 — Morning Without a Train
- **Conditions:** `always`
- **Summary:** Daylight makes Platform Zero look ordinary. Aoi sketches the old signal alignment for her observatory inventory and quietly corrects Ren when he calls Vega the North Star. She recognizes his grandmother’s house keychain.
- **Choices:**
  - Help hold her windblown charts. → `aoi_aff +1`; warm awkward introduction. → `C006`
  - Ask what she knows about midnight trains. → `evidence +1`; Aoi heard one from the sealed observatory. → `C006`
- **Clues:** `clue_observatory_heard_train`

### C006 — The Reporter in the Café
- **Conditions:** `always`
- **Summary:** Reina interrupts Ren’s breakfast with a recorder and asks whether he witnessed an unauthorized train. She has already connected his surname to the sealed accident file. Her directness feels invasive, but she turns the recorder off when he objects.
- **Choices:**
  - Give a careful, off-record description. → `reina_aff +1`, `privacy +1`; she reciprocates with her father’s case number. → `C007`
  - Refuse and ask how she knows his name. → `evidence +1`; learn a “Y. Takamori” appears in a redacted log. → `C007`
- **Clues:** `clue_y_takamori_log`, `clue_eiji_case`

### C007 — Two Invitations
- **Conditions:** `always`
- **Summary:** Aoi asks for audio help restoring an observatory tape. Reina asks Ren to inspect station ambience on a leaked recording. Both tasks happen before sunset, so this is rapport emphasis, not a route lock.
- **Choices:**
  - Go to the observatory archive first. → `aoi_aff +1`; next `C008`
  - Go to Reina’s press annex first. → `reina_aff +1`; next `C009`
- **Next:** The unchosen scene follows automatically; order changes dialogue only.

### C008 — Dust Constellations
- **Conditions:** reached first or second from `C007`
- **Summary:** Aoi leads Ren through the observatory archive. Dust on a removed wall photograph leaves silhouettes for four adults, though the caption lists three. A dead intercom whispers “little lighthouse,” a phrase that makes Ren cry without knowing why.
- **Choices:**
  - Admit the phrase affected him. → `aoi_aff +1`, `courage +1`; Aoi does not press. → next ordered scene / `C010`
  - Hide it and copy the caption. → `evidence +1`; obtain staff initials. → next ordered scene / `C010`
- **Clues:** `clue_fourth_staff_shadow`, `clue_little_lighthouse`

### C009 — The Missing Four Seconds
- **Conditions:** reached first or second from `C007`
- **Summary:** Reina plays a leaked station recording. Four seconds before the accident alarm are digitally blank, but Ren hears magnetic print-through beneath the silence: a woman saying “Mercy is armed.”
- **Choices:**
  - Teach Reina how print-through works. → `reina_aff +1`; she treats him as a partner, not source. → next ordered scene / `C010`
  - Request a copy before explaining. → `evidence +1`; obtain `clue_mercy_armed`. → next ordered scene / `C010`
- **Clues:** `clue_mercy_armed`, `clue_analog_survives_purge`

## Act C-II: Investigation and Bonds

### C010 — Tide Shrine Names
- **Conditions:** `always`
- **Summary:** Ren meets Aoi and Reina at the tide shrine; neither enjoys being surprised by the other. Mio joins after work and insists they share discoveries if they intend to survive. Four votive tablets for the accident victims have been replaced by blank wood.
- **Choices:**
  - Agree to a shared evidence pact. → `mio_trust +1`, `privacy +1`; group dialogue becomes more open. → `C011`
  - Keep personal memories separate from evidence. → `privacy +1`; Reina challenges but accepts the boundary. → `C011`
- **Clues:** `clue_blank_memorials`

### C011 — Inventory of Absences
- **Conditions:** `always`
- **Summary:** The group lists anomalies: missing names, altered photos, the impossible tape, and Platform Zero. Ren realizes all are absences with clean edges, suggesting deliberate removal rather than decay.
- **Choices:**
  - Prioritize people erased from records. → `aoi_aff +1`; unlock Satoru discussion. → `C012`
  - Prioritize whoever altered the systems. → `reina_aff +1`; unlock Kurogane lead. → `C012`
  - Prioritize train safety before either. → `mio_trust +1`; gain emergency brake hint. → `C012`
- **Clues:** `clue_deliberate_absence_pattern`

### C012 — Aoi’s Meteor Map
- **Conditions:** `always`
- **Summary:** On the seawall, Aoi demonstrates that the train’s arrivals align not with time but with meteor radiant angles. She confesses that her last clear memory of her father is him telling her not to look at the sky.
- **Choices:**
  - Say, “You can miss him and still question him.” → `aoi_aff +1`; Aoi keeps eye contact. → `C013`
  - Ask for the map’s raw measurements. → `evidence +1`; train prediction accuracy improves. → `C013`
- **Clues:** `clue_radiant_timetable`

### C013 — Reina’s Red Folder
- **Conditions:** `always`
- **Summary:** Reina reveals Eiji’s red safety folder. Most pages are duplicates, but pressure marks show a missing sheet once named an isolation relay in Tunnel 4. She admits she became a reporter because everyone called her father reckless.
- **Choices:**
  - Promise to help clear his name, not just solve Ren’s past. → `reina_aff +1`, set `press_pact = true`. → `C014`
  - Warn that proof may implicate other victims too. → `privacy +1`, `courage +1`; Reina respects the distinction. → `C014`
- **Clues:** `clue_isolation_relay`

### C014 — Mio’s Closed Gate
- **Conditions:** `always`
- **Summary:** Mio catches Ren testing the Platform Zero lock. She reveals one personal fact: every anniversary, the train returns her brother’s whistle polished clean. She will help only if Ren agrees Haru is not bait.
- **Choices:**
  - Return the whistle without asking to use it. → `mio_trust +2`; later receive it voluntarily. → `C015`
  - Ask whether Haru can answer questions. → `mio_trust -1`, `evidence +1`; learn echoes repeat until addressed by name. → `C015`
- **Clues:** `clue_echo_name_anchor`

### C015 — First Planned Boarding
- **Conditions:** `always`
- **Summary:** Using Aoi’s prediction, the group waits at midnight. The train opens one door. Mio can accompany only two people before the platform signal resets, forcing Ren to select a companion for this brief reconnaissance.
- **Choices:**
  - Board with Aoi. → `aoi_aff +1`; Aoi holds the red safety cord. → `C016`
  - Board with Reina. → `reina_aff +1`; Reina marks the door frame with chalk. → `C017`
  - Ask Mio to choose the safest plan. → `mio_trust +1`; Mio accompanies Ren while Aoi/Reina monitor. → `C018`
- **Effects common:** `train_marks +1`

### C016 — Car of Falling Stars
- **Conditions:** selected Aoi in `C015`
- **Summary:** The first car recreates the observatory dome under meteors. Aoi hears her father apologizing from behind a locked projection-room door. Ren stops her from opening it as dawn-light flickers impossibly at the far window.
- **Choices:**
  - Tell Aoi exactly what he heard. → `aoi_aff +1`, `memory_debt +1`; shared burden. → `C019`
  - Focus on copying the star sequence. → `evidence +1`; obtain seven-point sequence. → `C019`
- **Clues:** `clue_seven_point_sequence`

### C017 — Car of Redactions
- **Conditions:** selected Reina in `C015`
- **Summary:** Newspapers cover the second car. Every censored line becomes Ren’s face when Reina photographs it. A facsimile headline blames Eiji, but its publication date is one day before the accident.
- **Choices:**
  - Let Reina keep the impossible photograph. → `reina_aff +1`, `evidence +1`; image survives after exit. → `C019`
  - Tear down the accusatory headline. → `courage +1`; beneath it is the relay schematic. → `C019`
- **Clues:** `clue_prepared_cover_story`

### C018 — Conductor’s Shadow
- **Conditions:** selected Mio in `C015`
- **Summary:** Mio guides Ren to the coupling. A conductor-shaped shadow raises Haru’s whistle but speaks in a woman’s voice. Ren says the partial name “Yu—,” causing every carriage light to flare.
- **Choices:**
  - Finish: “Yui Takamori.” → set `yui_named = true`, `courage +1`, `memory_debt +1`. → `C019`
  - Step back and record the voice. → `evidence +1`, `mio_trust +1`; retain audio fragment. → `C019`
- **Clues:** `clue_yui_full_name`

### C019 — Dawn Check
- **Conditions:** after `C016`, `C017`, or `C018`
- **Summary:** Everyone exits before dawn, but Ren temporarily forgets the color of his grandmother’s front door. Mio identifies this as memory debt. Aoi is frightened for him; Reina is furious nobody disclosed the cost.
- **Choices:**
  - Admit that curiosity made him reckless. → `courage +1`, `privacy +1`; lowers interpersonal tension. → `C020`
  - Insist the clue was worth it. → `evidence +1`, `memory_debt +1`; harsher later callbacks. → `C020`
- **Clues:** `clue_memory_debt_rule`

### C020 — Ordinary Afternoon
- **Conditions:** `always`
- **Summary:** A deliberately low-stakes interlude at the shopping arcade. The group repairs a portable cassette player, buys festival sweets, and experiences ordinary chemistry away from the case.
- **Choices:**
  - Ask Aoi to choose music for the repair test. → `aoi_aff +1`; she chooses a song Yui once hummed. → `C021`
  - Help Reina win a rigged ring-toss game. → `reina_aff +1`; playful rivalry and shared prize. → `C021`
  - Carry Mio’s station supply box. → `mio_trust +1`; sibling-like teasing, explicitly non-romantic. → `C021`

### C021 — The Cassette Under the Floor
- **Conditions:** `always`
- **Summary:** The repaired player reacts near Ren’s sanded height chart. Beneath a floorboard lies Yui’s cassette labeled “For my little lighthouse, if forgetting wins.” The tape is tangled.
- **Choices:**
  - Let Aoi help unwind it by hand. → `aoi_aff +1`; careful intimacy. → `C022`
  - Let Reina document the seal before opening. → `reina_aff +1`, `evidence +1`; chain of custody established. → `C022`
  - Ask Mio to store the original after copying. → `mio_trust +1`, `privacy +1`; safer evidence. → `C022`
- **Clues:** `clue_yui_cassette`

### C022 — Yui’s First Message
- **Conditions:** `always`
- **Summary:** Ren restores one sentence: “If the train offers me back, ask what I chose—not what you wanted.” He finally remembers Yui’s laugh and collapses into grief. The scene centers care rather than clue extraction.
- **Choices:**
  - Accept Aoi’s quiet presence. → `aoi_aff +1`; she holds his sleeve until he initiates a hand clasp. → `C023`
  - Ask Reina to keep talking so he stays present. → `reina_aff +1`; she tells an honest story about Eiji. → `C023`
  - Ask for a minute alone, then return. → `courage +1`; validates solitary regulation without punishing romance. → `C023`
- **Effects common:** set `yui_named = true`
- **CG:** Ren with cassette, companions framed in doorway.

## Act C-III: Festival, Betrayal, and Route Lock

### C023 — Corporate Seal
- **Conditions:** `always`
- **Summary:** Reina identifies a Kurogane Rail inventory seal on the cassette case. Aoi recognizes the serial family as observatory optics equipment. Their fathers’ stories intersect with Yui’s.
- **Choices:**
  - Share every recovered detail now. → `privacy +1`, `evidence +1`; group unity. → `C024`
  - Withhold Yui’s personal sentence from the case notes. → `privacy +1`, `aoi_aff +1`; Reina initially bristles but accepts. → `C024`
- **Clues:** `clue_kurogane_optics_link`

### C024 — Tunnel 4
- **Conditions:** `always`
- **Summary:** The group enters the sealed rail tunnel. They find the isolation relay welded shut in the ON position and a maintenance camera housing pointed toward it.
- **Choices:**
  - Photograph before touching anything. → set `relay_photo = true`, `evidence +2`, `reina_aff +1`. → `C025`
  - Try to force the relay open. → `courage +1`, `memory_debt +1`; trigger a brief train overlap. → `C025`
  - Follow Mio’s cable map to the manual bypass. → `mio_trust +1`, `evidence +1`; safer true-route option foreshadowed. → `C025`
- **Clues:** `clue_relay_welded_on`

### C025 — The Day Ren Lost
- **Conditions:** `always`
- **Summary:** Ren wakes at home with wet shoes and no memory of leaving the tunnel. Aoi and Reina both claim he called them at 00:00, but each call contains different words. The train can simulate branches using stolen memories.
- **Choices:**
  - Compare both recordings without deciding which is “real.” → `evidence +1`, `privacy +1`; identify identical background brake tone. → `C026`
  - Trust the call that feels kinder. → affinity `+1` to selected heroine, `memory_debt +1`; train learns Ren prefers comforting illusions. → `C026`
- **Clues:** `clue_branch_simulation`, `clue_brake_tone`

### C026 — Aoi’s Unsent Letter
- **Conditions:** `always`
- **Summary:** Aoi shows Ren a letter to her father she has rewritten every year. She fears he caused the accident. She asks whether Ren would still want Yui remembered if Yui made the wrong choice.
- **Choices:**
  - “Yes. Love isn’t an acquittal.” → `aoi_aff +1`, `courage +1`; key good-route philosophy. → `C027`
  - “I don’t know yet, but I won’t lie to you.” → `aoi_aff +1`, `privacy +1`; alternate honest response. → `C027`
  - “Some truths only reopen wounds.” → `memory_debt +1`; Aoi withdraws. → `C027`

### C027 — Reina’s Unpublished Draft
- **Conditions:** `always`
- **Summary:** Reina lets Ren read her draft. It names Kurogane but also describes Ren’s breakdown and Aoi’s family suspicion without consent. She asks for a brutal edit.
- **Choices:**
  - Mark the private passages and explain why. → `reina_aff +1`, `privacy +2`; Reina revises without defensiveness. → `C028`
  - Praise the exposé and ignore the personal cost. → `evidence +1`, `privacy -2`; future bad-ending pressure. → `C028`
  - Ask to co-write a consent policy for sources. → `reina_aff +1`, `privacy +1`, set `consent_protocol = true`. → `C028`

### C028 — Star Festival Blackout
- **Conditions:** `always`
- **Summary:** During the festival, every lantern goes dark. The impossible train appears along the seawall with no tracks, and townspeople forget loved ones for several minutes. Ren sees Yui in a carriage window.
- **Choices:**
  - Call Yui’s full name and stay outside. → `courage +1`; preserve memories. → `C029`
  - Chase the moving train. → `train_marks +1`, `memory_debt +1`; obtain a fragment of Yui’s sleeve ribbon. → `C029`
  - Help Mio guide confused townspeople first. → `mio_trust +1`, `privacy +1`; civic stakes foregrounded. → `C029`
- **CG:** Trackless train among dark festival lanterns.

### C029 — The Accusation
- **Conditions:** `always`
- **Summary:** A manipulated echo broadcasts Satoru saying “begin the purge,” then Eiji saying “keep the train moving.” Aoi and Reina nearly turn on each other. Ren must frame uncertainty without dismissing either woman’s pain.
- **Choices:**
  - Point out the audio cuts and demand verification. → `evidence +1`; both regain focus. → `C030`
  - Stand beside Aoi and reject blame without proof. → `aoi_aff +1`; Reina feels sidelined but remains. → `C030`
  - Stand beside Reina and prioritize the logs. → `reina_aff +1`; Aoi feels isolated but remains. → `C030`
  - Ask Mio what Haru’s brake tone proves. *(requires `mio_trust >= 3`)* → `evidence +2`; recordings occurred in different minutes. → `C030`
- **Clues:** `clue_spliced_accusation`

### C030 — Platform Zero Ultimatum
- **Conditions:** `always`
- **Summary:** Kurobe’s legal representative announces the observatory will be demolished after the festival and all artifacts removed. That night the train prints one ticket in Ren’s name, valid for two passengers.
- **Choices:**
  - Give Aoi the ticket for safekeeping. → `aoi_aff +1`, set `promised_return = true`. → `C031`
  - Give Reina the ticket as evidence under seal. → `reina_aff +1`, set `press_pact = true`. → `C031`
  - Give Mio the ticket and ask her to enforce the rules. → `mio_trust +1`; route choice remains open. → `C031`

### C031 — Whom to Meet at Midnight (Route Lock)
- **Conditions:** `always`; options gated as in §6.3
- **Summary:** Ren knows the next boarding will expose the companion’s deepest memory and cannot pretend the choice is merely tactical. He chooses whom to trust with his missing night—or, after both good clears, chooses to follow the impossible memory of both paths.
- **Choices:**
  - “Aoi, meet me under the observatory dome.” *(requires `aoi_aff >= 2`)* → `route_focus = aoi` → `C032`
  - “Reina, meet me beside the printing press.” *(requires `reina_aff >= 2`)* → `route_focus = reina` → `C033`
  - “I remember two dawns that never happened.” *(requires `true_route_unlocked`)* → `route_focus = true` → `T001`
  - “I need one more honest conversation.” *(if neither affinity qualifies)* → `C034`

### C032 — Aoi Route Threshold
- **Conditions:** `route_focus == aoi`
- **Summary:** Under the dome, Ren explicitly tells Aoi he chose her for more than her knowledge. She admits she hoped he would, but asks him not to make her responsible for all his memories. They agree to investigate as equal adults.
- **Choices:**
  - “Then stop me when I turn you into an answer.” → `aoi_aff +1`, `privacy +1`. → `A001`
  - “Promise we both come back before dawn.” → set `promised_return = true`, `courage +1`. → `A001`

### C033 — Reina Route Threshold
- **Conditions:** `route_focus == reina`
- **Summary:** At the press annex, Ren says he trusts Reina with the truth but not ownership of it. Reina admits she wants him beside her even if the story disappears. They define partnership and source consent before boarding.
- **Choices:**
  - Seal the pact with a handshake that lingers. → `reina_aff +1`, set `press_pact = true`. → `R001`
  - Ask her to promise people come before headlines. → `privacy +1`; she promises actions, not perfection. → `R001`

### C034 — One More Honest Conversation
- **Conditions:** `aoi_aff < 2 && reina_aff < 2`
- **Summary:** The route-lock safety valve. Ren recognizes that he has treated everyone as functions in his mystery. He makes one sincere call, with no clue reward.
- **Choices:**
  - Apologize to Aoi for keeping emotional distance. → `aoi_aff +2` → `C031`
  - Apologize to Reina for treating her trust as evidence. → `reina_aff +2` → `C031`
- **Note:** This prevents a dead-end while clearly naming the behavior that caused it.

---

# 9. Aoi Route Scene Graph — 22 Scenes

## A-I: The Shape of a Person

### A001 — A Private Sky
- **Conditions:** `route_focus == aoi`
- **Summary:** Aoi opens the observatory for an overnight cataloguing session. Away from the group, she tells Ren she remembers meeting him once as a child but cannot remember his face—only that he called her “the girl who knew where north was.”
- **Choices:**
  - Joke that she still corrects him. → `aoi_aff +1`; gentle ease. → `A002`
  - Admit he is afraid of what their missing memory contains. → `aoi_aff +1`, `courage +1`. → `A002`

### A002 — Parallax
- **Conditions:** `always in Aoi route`
- **Summary:** Aoi explains parallax: one object understood from two positions. They decide to compare her father’s notes and Yui’s tape without treating either as complete.
- **Choices:**
  - Let Aoi lead the notebook analysis. → `aoi_aff +1`; honors expertise. → `A003`
  - Build an audio timeline while she maps stars. → `evidence +1`; complementary partnership. → `A003`
- **Clues:** `clue_parallax_method`

### A003 — The Locked Study
- **Conditions:** `always`
- **Summary:** At the Mizuno cottage, Aoi opens Satoru’s study for the first time. A family planetarium projector contains a hidden strip of meteor-glass and a note: “Identity is not pain; do not calibrate them as one.”
- **Choices:**
  - Ask before reading the rest aloud. → `privacy +1`, `aoi_aff +1`. → `A004`
  - Immediately compare the glass with observatory records. → `evidence +1`; identify Lens shard. → `A004`
- **Clues:** `clue_identity_not_pain`

### A004 — Tea for Three
- **Conditions:** `always`
- **Summary:** Aoi’s mother Sachiko serves tea and treats Ren as if she once knew him. She finally admits Satoru feared Polaris could preserve trauma so perfectly that a victim could never heal.
- **Choices:**
  - Defend neither Satoru nor the project; listen. → `aoi_aff +1`, `privacy +1`. → `A005`
  - Ask Sachiko for the sealed resignation letter. → `evidence +1`; she provides it if `privacy >= 1`, otherwise refuses and scene continues. → `A005`
- **Clues:** `clue_satoru_resigned`

### A005 — Meteor Shower Rehearsal
- **Conditions:** `always`
- **Summary:** Ren and Aoi calibrate the dome manually. In darkness, they share headphones and hear their younger selves arguing about star names, then Yui laughing. The intimacy is tender but unsettling.
- **Choices:**
  - Remove the headphones and ask how Aoi feels now. → `aoi_aff +1`, `memory_debt -1` (min 0). → `A006`
  - Keep listening for more context. → `evidence +1`, `memory_debt +1`; hear Satoru’s warning code. → `A006`
- **Clues:** `clue_warning_code_polaris_red`

### A006 — Promise at the Seawall
- **Conditions:** `always`
- **Summary:** Aoi confesses that silence has become her method of keeping people from leaving. Ren can answer with commitment or comforting vagueness.
- **Choices:**
  - “I can’t promise nothing changes. I can promise I’ll tell you before I go.” → `aoi_aff +2`, set `promised_return = true`. → `A007`
  - “I’m not going anywhere.” → `aoi_aff +1`; later tested as an impossible promise. → `A007`
  - Change the subject to the timetable. → `evidence +1`; emotional distance. → `A007`

### A007 — The Glass Constellation
- **Conditions:** `always`
- **Summary:** Lens-shard reflections reveal seven star points matching the train-car sequence from `C016` or recoverable through Aoi’s map. The seventh point is not a star but Platform Zero.
- **Choices:**
  - Trace it together, hand over hand. → `aoi_aff +1`; understated physical closeness. → `A008`
  - Photograph and call Mio immediately. → `mio_trust +1`, `evidence +1`. → `A008`
- **Clues:** `clue_platform_as_seventh_point`

### A008 — Father in the Dome
- **Conditions:** `always`
- **Summary:** At midnight, Satoru’s echo appears under the projector. He apologizes to Aoi, but repeats her childhood wish word for word, revealing the train is building the “perfect father” from her own memories.
- **Choices:**
  - Point out the repetition gently. → `courage +1`, `aoi_aff +1`; Aoi rejects the illusion herself. → `A009`
  - Let her accept the embrace. → `memory_debt +1`; the echo gains strength. → `A009`
- **Clues:** `clue_echoes_use_witness_memory`

## A-II: Love Without a Shrine

### A009 — What Aoi Wanted
- **Conditions:** `always`
- **Summary:** Shaken, Aoi says she wanted one uncomplicated apology. Ren admits he wanted Yui returned without asking what that would cost. Their grief becomes mutual rather than comparative.
- **Choices:**
  - Hold out his hand and let Aoi choose. → `aoi_aff +1`, `privacy +1`; she takes it. → `A010`
  - Offer an embrace verbally. → `aoi_aff +1`; she accepts if `aoi_aff >= 6`, otherwise asks to walk beside him. → `A010`

### A010 — Satoru’s Real Notebook
- **Conditions:** `always`
- **Summary:** Mio helps find a notebook hidden inside the station telescope display. Satoru’s authentic notes describe separating an identity signature (name, chosen bonds, self-narration) from traumatic content.
- **Choices:**
  - Credit Mio and include Haru in the working theory. → `mio_trust +1`; potential `haru_token` later. → `A011`
  - Focus entirely on extracting the formula. → `evidence +1`; faster but colder. → `A011`
- **Effects:** set `identity_formula = true`
- **Clues:** `clue_identity_formula`

### A011 — Constellation of Small Things
- **Conditions:** `identity_formula == true`
- **Summary:** To test the formula safely, Aoi lists memories that define her without her father: burnt coffee, beach glass, stubborn houseplants, and Ren misnaming stars. Ren contributes non-traumatic memories of Yui.
- **Choices:**
  - Include the first moment he noticed Aoi’s kindness. → `aoi_aff +1`; romantic recognition. → `A012`
  - Include a memory of choosing to return after being alone. → `courage +1`; supports selfhood theme. → `A012`

### A012 — Almost Kiss, Interrupted Bell
- **Conditions:** `always`; romantic staging variant requires `aoi_aff >= 5`
- **Summary:** While sheltering from rain in the observatory stairwell, Aoi and Ren nearly kiss. The tide-shrine bell rings though there is no wind, and Aoi pulls back—not from rejection, but because the train just took another town memory.
- **Choices:**
  - Say, “We can come back to this.” → `aoi_aff +1`, `privacy +1`; no pressure. → `A013`
  - Ask if she changed her mind. → honest clarification, no penalty; she says no, but timing matters. → `A013`
- **Note:** If `aoi_aff < 5`, use a close conversation without near-kiss; same choices adapted.

### A013 — The Town Forgets the Observatory
- **Conditions:** `always`
- **Summary:** By morning, locals insist the hill has always been empty. Only the core group remembers the building. Demolition crews cannot perceive it, proving the siphon is accelerating.
- **Choices:**
  - Preserve public landmarks through photos and names. → `evidence +1`, `privacy +1`. → `A014`
  - Rush directly into the train for answers. → `memory_debt +1`, `courage +1`. → `A014`

### A014 — Second Boarding: The Planetarium Car
- **Conditions:** `always`
- **Summary:** Ren and Aoi board a carriage containing a perfect miniature sky. Their childhood selves sit apart, frightened, while Satoru and Yui argue over Mercy. Aoi can approach her younger echo only if Ren does not speak for her.
- **Choices:**
  - Ask Aoi what she wants to say. → `aoi_aff +1`, `privacy +1`; she tells herself the accident was not her fault. → `A015`
  - Tell young Aoi her father loved her. → `aoi_aff -1`, `memory_debt +1`; imposes an answer she did not choose. → `A015`
- **Clues:** `clue_mercy_separates_links`

### A015 — Satoru’s Confession
- **Conditions:** `always`
- **Summary:** The authentic Satoru echo stabilizes when Aoi names him and cites a memory the train did not stage. He admits he accepted dangerous funding, tried to stop the test too late, and designed Mercy but did not activate it.
- **Choices:**
  - Let Aoi question him without interruption. → `aoi_aff +1`, `echo_consent +1`; complete testimony. → `A016`
  - Demand Yui’s role immediately. → `evidence +1`; Satoru destabilizes before giving full emotional closure. → `A016`
- **Clues:** `clue_satoru_did_not_activate_mercy`

### A016 — Dawn Handhold
- **Conditions:** `always`
- **Summary:** The exit door vanishes. Aoi uses the identity formula by naming who she is now; Ren answers with his own chosen memories. Their clasped hands become the stable reference that reveals the door.
- **Choices:**
  - Spend a precious minute helping Satoru choose whether to remain. → `memory_debt +1`, `echo_consent +1`, `aoi_aff +1`. → `A017`
  - Leave immediately as promised. → `courage +1`; safer but Satoru remains unresolved. → `A017`
- **CG:** Ren and Aoi holding hands under a dissolving artificial sky.

### A017 — The Argument Under Daylight
- **Conditions:** `always`
- **Summary:** Ren proposes using the formula to strip pain from every echo. Aoi objects: removing pain without consent repeats Mercy’s violation. Their first serious romantic conflict asks whether rescue can become erasure.
- **Choices:**
  - Listen and revise the plan around consent. → `aoi_aff +1`, `privacy +2`; unlock good threshold support. → `A018`
  - Insist survival justifies the method. → `aoi_aff -2`, `privacy -1`; pushes bad ending. → `A018`
  - Walk away to avoid saying something cruel. → `promised_return` determines later repair; no immediate effect. → `A018`

### A018 — Return or Silence
- **Conditions:** `always`
- **Summary:** If Ren walked away, he must honor or break his promise. Otherwise this scene becomes a planned reconciliation. Aoi states clearly that she wants Ren, not merely his shared grief, but cannot be his excuse to stop choosing.
- **Choices:**
  - Return before midnight and apologize specifically. → `aoi_aff +2`, set `aoi_truth = true`. → `A019`
  - Share Yui’s full message and admit his fear. → `aoi_aff +1`, `courage +1`, set `aoi_truth = true`. → `A019`
  - Leave a note and board alone. → `memory_debt +2`, set `aoi_truth = false`. → `A019`

## A-III: Endings

### A019 — The Seventh Point
- **Conditions:** `always`
- **Summary:** The train and observatory overlap. Aoi can use the Lens shard to give Satoru’s echo a choice: release his testimony and dissolve, or remain as a fading private memory. Ren must decide whether to follow Aoi’s consent-based plan or force a purge.
- **Choices / ending dispatch:**
  - “We ask him, and we accept his answer.” → if `aoi_aff >= 7 && identity_formula && aoi_truth && privacy >= 2 && memory_debt <= 3`, go `A022`; else go `A021`.
  - “Erase the pain before the loop takes you.” → `A020`.
  - “Stay with him. I’ll hold the train alone.” → if `promised_return && courage >= 3`, `A021`; otherwise `A020`.

### A020 — Bad Ending: **Fixed Star**
- **Conditions:** dispatched from `A019`
- **Summary:** Ren forces the identity formula through the Lens. Satoru’s pain disappears—and with it the choices that made his echo coherent. The train collapses around Ren, who becomes its new anchor. Months later, Aoi visits Platform Zero and hears Ren promise forever in exactly the words she once wanted. She recognizes the repetition, whispers that it is not him, and walks away in tears as the train continues.
- **Persistent effects:** add `ENDING_A_BAD` to `ending_gallery`; do **not** set route-clear fragments.
- **Return:** title screen / route select.

### A021 — Bittersweet Ending: **A Sky with One Star Missing**
- **Conditions:** dispatched from `A019` without good threshold, or sacrificial choice with adequate courage
- **Summary:** Aoi gains an honest farewell with Satoru, but Ren pays excessive memory debt or fails to share his full truth. The loop quiets for years, not forever. Ren and Aoi choose each other cautiously, yet he can no longer remember Yui’s voice. Aoi writes it down from her own memory and reads it when he asks. Their final embrace is loving but shadowed by the knowledge that someone else must finish the work.
- **Persistent effects:** add `ENDING_A_BITTERSWEET`; no `fragment_star`.
- **Romance status:** Together, with unresolved supernatural stakes.

### A022 — Good Ending: **The Stars We Choose**
- **Conditions:** `aoi_aff >= 7`, `identity_formula == true`, `aoi_truth == true`, `privacy >= 2`, `memory_debt <= 3`, and consent choice at `A019`
- **Summary:** Satoru chooses to release his technical testimony and let his private memories dissolve with him. Aoi tells him she loves him but will not orbit his absence. The observatory loop separates from the passenger echoes, weakening the train. At dawn, Ren tells Aoi he wants a future made of ordinary days as well as mysteries. She kisses him once, then laughs when he calls the morning star a star. Months later they restore the hill as a public memorial and small astronomy center. A final reflection in the telescope shows an ink-black ticket—evidence another truth remains.
- **Persistent effects:** set `aoi_good_clear = true`, `fragment_star = true`; add `ENDING_A_GOOD`.
- **Romance status:** Ren and Aoi are explicitly a committed couple.
- **True-route seed:** The identity formula persists as an intuition across resets.

---

# 10. Reina Route Scene Graph — 22 Scenes

## R-I: What Counts as Evidence

### R001 — Off the Record
- **Conditions:** `route_focus == reina`
- **Summary:** Reina locks her recorder in a desk drawer before asking Ren what he remembers of Yui. The gesture matters more than reassurance. Ren notices her hands shake when Eiji’s name appears in the notes.
- **Choices:**
  - Tell her the complete memory fragment. → `reina_aff +1`, set `reina_truth = true`. → `R002`
  - Ask what she is afraid the story will prove. → `reina_aff +1`, `courage +1`; she admits Eiji may have made mistakes. → `R002`

### R002 — Byline Pact
- **Conditions:** `always in Reina route`
- **Summary:** They draft rules: verify supernatural claims physically, separate public evidence from private memory, and obtain explicit consent before quoting echoes or survivors.
- **Choices:**
  - Sign as co-investigator. → `reina_aff +1`, set `press_pact = true`. → `R003`
  - Add a right-to-withdraw clause. → `privacy +1`, set `consent_protocol = true`. → `R003`
- **Clues:** `clue_reporting_protocol`

### R003 — Contact Sheet
- **Conditions:** `always`
- **Summary:** In a borrowed darkroom, Reina develops the impossible carriage photograph. A second image emerges beneath it: Kurobe beside the Tunnel 4 relay on the afternoon before the accident.
- **Choices:**
  - Preserve negatives and make checksummed copies. → `evidence +2`; strong chain of custody. → `R004`
  - Crop out Ren’s distorted face before copying. → `privacy +1`, `reina_aff +1`; public/private separation. → `R004`
- **Clues:** `clue_kurobe_at_relay`

### R004 — Interview with a Liar
- **Conditions:** `always`
- **Summary:** Former technician Daichi Noma repeats the official fire story but unconsciously taps the train’s brake rhythm. Reina can corner him; Ren can recognize a trauma response.
- **Choices:**
  - Pause the interview and offer water. → `privacy +1`, `reina_aff +1`; Noma voluntarily names the remote purge order. → `R005`
  - Present the photograph and demand a confession. → `evidence +1`, `privacy -1`; he gives a partial quote, then ends interview. → `R005`
- **Clues:** `clue_remote_purge_order`

### R005 — A Story Before It Is Ready
- **Conditions:** `always`
- **Summary:** Reina’s editor demands a sensational train article within 24 hours. Publishing now could stop demolition but expose Ren and Aoi. Reina asks Ren to decide with her, not for her.
- **Choices:**
  - Publish a narrow infrastructure hold story. → `reina_aff +1`, `privacy +1`; delays demolition without supernatural claims. → `R006`
  - Leak everything anonymously. → `evidence +1`, `privacy -2`; public attention feeds the train. → `R006`
  - Publish nothing yet and risk demolition. → `courage +1`; preserves trust, increases time pressure. → `R006`

### R006 — Midnight Stakeout
- **Conditions:** `always`
- **Summary:** Ren and Reina stake out Platform Zero in a cramped maintenance booth. Banter gives way to Reina admitting she remembers Eiji packing to leave the family, though she does not know if the memory is real or train-made.
- **Choices:**
  - Believe her feeling without declaring the memory factual. → `reina_aff +1`, `privacy +1`. → `R007`
  - Analyze inconsistencies immediately. → `evidence +1`; useful but emotionally distancing. → `R007`

### R007 — The Camera That Remembers
- **Conditions:** `always`
- **Summary:** Eiji’s old analog camera advances by itself when the train arrives. Its undeveloped roll contains present-day images, proving objects exposed during the accident can retain loop states.
- **Choices:**
  - Give Reina control of her father’s camera. → `reina_aff +1`; she chooses when to use it. → `R008`
  - Load it and photograph the destination board. → `evidence +1`, `train_marks +1`; captures “NOT YET.” → `R008`
- **Clues:** `clue_objects_retain_loop_states`

### R008 — Car of Unprinted Truths
- **Conditions:** `always`
- **Summary:** Ren and Reina board. Every compartment contains a different article Reina could publish: hero father, villain father, miraculous survivors. None cite sources. The train tempts her with certainty.
- **Choices:**
  - Ask which version frightens her most. → `reina_aff +1`; she says the version that sells. → `R009`
  - Burn the false front pages in the carriage stove. → `courage +1`; hidden rail log appears in ash. → `R009`
- **Clues:** `clue_train_rewards_certainty`

## R-II: Truth With Permission

### R009 — Eiji’s Voice
- **Conditions:** `always`
- **Summary:** Eiji’s echo appears and confesses to “keeping the train moving.” Reina nearly accepts this as guilt. Ren recognizes the phrase as an evacuation command, not sabotage.
- **Choices:**
  - Ask Eiji whom he was evacuating. → `evidence +1`, `echo_consent +1`; names observatory staff and four adolescents. → `R010`
  - Tell Reina her father is innocent before verifying. → `reina_aff +1`, but `evidence -1` (min 0); emotionally kind, journalistically weak. → `R010`
- **Clues:** `clue_evacuation_command`

### R010 — Manual Brake
- **Conditions:** `always`
- **Summary:** Mio identifies Haru’s brake rhythm in Eiji’s statement. She gives Ren the whistle if `mio_trust >= 3`; otherwise she accompanies them to ensure it is not misused.
- **Choices:**
  - Invite Mio to set the terms of contacting Haru. → `mio_trust +1`, set `haru_token = true`. → `R011`
  - Treat the whistle as evidence and bag it. → `evidence +1`, `mio_trust -1`; no `haru_token`. → `R011`
- **Clues:** `clue_haru_held_manual_brake`

### R011 — Pressroom Rain
- **Conditions:** `always`
- **Summary:** A typhoon traps Ren and Reina in the annex. She admits she envies his ability to say “I don’t know”; her career feels built on sounding certain. He admits he envies her willingness to act.
- **Choices:**
  - Tell her courage includes revising the story. → `reina_aff +1`, `courage +1`. → `R012`
  - Share a quiet dance to the repaired cassette’s instrumental section. → `reina_aff +1`; romantic breathing space. → `R012`

### R012 — Kiss and Correction
- **Conditions:** `reina_aff >= 5`
- **Summary:** Reina impulsively kisses Ren after they survive a power surge, then immediately checks whether he wanted it. He did, but the scene emphasizes mutual clarity rather than adrenaline as consent.
- **Choices:**
  - Kiss her back after answering clearly. → `reina_aff +1`, `privacy +1`. → `R013`
  - Ask to wait until the investigation is over. → `reina_aff +1`; she appreciates honesty; romance remains active. → `R013`
- **Note:** If affinity is lower, replace kiss with a charged handhold and direct conversation.

### R013 — The Leak
- **Conditions:** `always`
- **Summary:** Reina’s editor receives private audio from Ren’s memory session. Evidence points to a scheduled cloud backup, not Reina, but Ren’s first reaction can strengthen or fracture trust.
- **Choices:**
  - Ask what happened before accusing her. → `reina_aff +1`, `privacy +1`; discover Kurogane subpoena exploit. → `R014`
  - Accuse her of choosing the story. → `reina_aff -2`; she proves innocence but trust is damaged. → `R014`
  - Shut down every copy together. → `evidence -1`, `privacy +2`; sacrifice evidence to protect people. → `R014`
- **Clues:** `clue_kurogane_monitoring`

### R014 — Kurobe’s Offer
- **Conditions:** `always`
- **Summary:** Kurobe contacts Reina by video. He offers Eiji’s “exoneration” and a career-making exclusive if she surrenders Yui’s tape and calls the train a grief hallucination.
- **Choices:**
  - Keep him talking under legally permitted recording rules. → `evidence +2`, `reina_aff +1`; capture admission that relay bypass was authorized. → `R015`
  - Reject him immediately. → `courage +1`; morally clear but less evidence. → `R015`
  - Pretend to accept without telling Ren. → `evidence +1`, `privacy -1`; creates later trust test. → `R015`
- **Clues:** `clue_kurobe_authorized_bypass`

### R015 — The Missing Sheet
- **Conditions:** `always`
- **Summary:** Pressure-mark analysis reconstructs Eiji’s missing report: the rail line and Lens formed a feedback circuit. Cutting both simultaneously can stop the loop, but a raw shutdown would erase every echo and all encoded testimony.
- **Choices:**
  - Seek a method preserving consenting testimony. → `privacy +1`, set `consent_protocol = true`. → `R016`
  - Accept erasure as the price of stopping harm. → `courage +1`, `privacy -1`; bad/bittersweet pressure. → `R016`
- **Clues:** `clue_dual_shutdown`, `clue_raw_shutdown_erases_evidence`

### R016 — Interviewing the Dead
- **Conditions:** `always`
- **Summary:** Reina proposes treating echoes as sources with agency. She reads rights and limitations aloud before questioning Eiji. His echo becomes more coherent because he can decline.
- **Choices:**
  - Let Eiji exclude his private message to the family. → `privacy +2`, `echo_consent +1`, `reina_aff +1`. → `R017`
  - Push for the emotionally powerful quote. → `evidence +1`, `privacy -2`; echo destabilizes. → `R017`
- **Effects:** if consent respected, `consent_protocol = true`

### R017 — Eiji Was Leaving
- **Conditions:** `always`
- **Summary:** Eiji confirms Reina’s memory: he packed a bag, but to move the family away after exposing Kurogane, not abandon them. He also admits he hid danger from them. The truth is neither ideal nor cruel.
- **Choices:**
  - Allow Reina to end the interview herself. → `reina_aff +1`, `echo_consent +1`. → `R018`
  - Ask for Yui’s role before time runs out. → `evidence +1`; learn Yui armed Mercy. → `R018`
- **Clues:** `clue_yui_armed_mercy_partial`

### R018 — Scope of the Story
- **Conditions:** `always`
- **Summary:** Before the final boarding, Reina shows Ren the revised exposé. It can name Kurogane using physical evidence while anonymizing survivors and keeping non-consenting echo memories out.
- **Choices:**
  - Approve with explicit boundaries. → `reina_aff +1`, `privacy +1`, set `reina_truth = true`. → `R019`
  - Give her every memory to publish for maximum impact. → `evidence +1`, `privacy -2`. → `R019`
  - Ask her to bury the story entirely. → `reina_aff -1`; undermines her core need. → `R019`

## R-III: Endings

### R019 — Deadline at Dawn
- **Conditions:** `always`
- **Summary:** Kurobe’s recovery team enters Tunnel 4 while the train manifests. Reina can transmit a verified evidence package, but only Ren can keep the carriage stable long enough. Eiji asks whether his private farewell will be included.
- **Choices / ending dispatch:**
  - “Only what each person consented to. Publish the proof.” → if `reina_aff >= 7 && evidence >= 6 && privacy >= 2 && consent_protocol && reina_truth`, go `R022`; else `R021`.
  - “Give them everything. Make it impossible to ignore.” → `R020`.
  - “Destroy the archive; save the living.” → if `courage >= 3 && memory_debt <= 3`, `R021`; otherwise `R020`.

### R020 — Bad Ending: **Front Page Ghost**
- **Conditions:** dispatched from `R019`
- **Summary:** The unfiltered memory archive goes viral. Public attention supplies millions of unresolved “tickets,” letting the train appear across the region. Reina wins awards for the story but loses the ability to distinguish her memories from downloaded ones. Ren finds her alone in the pressroom interviewing an empty chair; she calls him by her father’s name. The final headline types itself: EVERYONE REMEMBERS, NO ONE KNOWS WHY.
- **Persistent effects:** add `ENDING_R_BAD`; no good-clear fragments.

### R021 — Bittersweet Ending: **The Unpublished Truth**
- **Conditions:** dispatched from `R019` without good thresholds, or ethical destruction choice
- **Summary:** Ren and Reina destroy the active archive to prevent the train spreading. Kurobe’s circumstantial crimes become public, but Eiji’s full exoneration remains legally uncertain. Reina leaves the newspaper and begins an independent oral-history project with strict consent. She and Ren choose a relationship built on candor, yet both wonder whether silence protected people or merely repeated the cover-up. A station bell in another town suggests the loop is dormant, not ended.
- **Persistent effects:** add `ENDING_R_BITTERSWEET`; no `fragment_ink`.
- **Romance status:** Together, with professional and mystery uncertainty.

### R022 — Good Ending: **Ink Before Dawn**
- **Conditions:** `reina_aff >= 7`, `evidence >= 6`, `privacy >= 2`, `consent_protocol == true`, `reina_truth == true`, ethical publish choice
- **Summary:** Reina transmits a narrow, verifiable package: relay photographs, Kurobe’s recorded admission, Eiji’s technical testimony by consent, and redacted survivor accounts. Eiji chooses to keep his family farewell private and dissolves at peace. Authorities halt demolition and open a criminal inquiry. At sunrise, Reina tells Ren the article matters, but not more than the person who trusted her. Their deliberate second kiss is quiet, mutual, and interrupted by the presses starting. Months later they work from different cities but meet in Hoshikawa every weekend. A star-shaped scratch appears on Eiji’s camera lens—evidence another truth remains.
- **Persistent effects:** set `reina_good_clear = true`, `fragment_ink = true`; add `ENDING_R_GOOD`.
- **Romance status:** Ren and Reina are explicitly a committed couple.
- **True-route seed:** The consent protocol persists as an intuition across resets.

---

# 11. True Route Scene Graph — 20 Scenes

## Unlock and continuity premise

The True Route appears at `C031` only when both `fragment_star` and `fragment_ink` persist. It is not a literal New Game Plus conversation in which Ren boasts of dating both women. Instead, he experiences the completed routes as emotionally vivid **possible histories encoded by the train**. Aoi and Reina receive fragments of the same possibilities and recognize that each path contained authentic choices, but none occurred in the current run. The route insists on an honest, exclusive present-tense romantic choice.

## T-I: Two Impossible Dawns

### T001 — Memory of Two Mornings
- **Conditions:** `true_route_unlocked == true`, selected at `C031`
- **Summary:** Ren remembers Aoi kissing him beneath the observatory and Reina kissing him beside the press—two mutually exclusive dawns. He refuses the train’s invitation to select whichever memory feels best and tells Aoi, Reina, and Mio everything.
- **State normalization:** set `route_focus = true`; set `identity_formula = fragment_star`; set `consent_protocol = fragment_ink`; set `memory_debt = max(0, memory_debt - 1)`; retain common-route affinities/trust/evidence.
- **Choices:**
  - Describe both paths without claiming either as current fact. → `privacy +1`, `courage +1`. → `T002`
  - Ask each woman to verify what fragments she remembers. → `evidence +1`; both recall different sensory details. → `T002`
- **Clues:** `clue_routes_are_train_possibilities`

### T002 — No One Is a Route
- **Conditions:** `always in True Route`
- **Summary:** Aoi is hurt by the intimacy of the other possibility; Reina masks the same discomfort with jokes. Mio bluntly states that none of them owe Ren the roles they played in unrealized histories. Ren must agree rather than seek absolution.
- **Choices:**
  - “You are not memories I get to keep. We choose from here.” → `privacy +2`, `aoi_aff +1`, `reina_aff +1`. → `T003`
  - Ask for time and focus only on the case. → `courage +1`; romance choice delayed without penalty. → `T003`

### T003 — Combined Method
- **Conditions:** `identity_formula && consent_protocol`
- **Summary:** The star fragment supplies a way to separate identity from traumatic content; the ink fragment supplies consent and verification rules. Combined, they can export chosen testimony while allowing private memories and echo identities to release.
- **Choices:**
  - Put Mio in charge of the release order. → `mio_trust +1`; practical safety improves. → `T004`
  - Build a four-person checklist with veto power. → `privacy +1`, `evidence +1`; collective governance. → `T004`
- **Clues:** `clue_combined_release_method`

### T004 — Yui’s Second Message
- **Conditions:** `always`
- **Summary:** The restored cassette now plays a hidden reverse track: “Ren was the anchor because he remembered me with joy before he remembered the accident.” Yui chose his identity signature to stabilize Mercy.
- **Choices:**
  - Accept that love was used without consent. → `courage +1`; nuanced response. → `T005`
  - Defend Yui immediately. → `memory_debt +1`; later Yui confrontation harder. → `T005`
  - Condemn Yui as solely responsible. → `privacy -1`; ignores coercive context. → `T005`
- **Clues:** `clue_ren_is_anchor`, `clue_yui_used_joy_signature`

### T005 — Mio Says No
- **Conditions:** `always`
- **Summary:** The plan requires Haru’s whistle to call the conductor echo. Mio refuses. Rather than a persuasion minigame, the scene asks whether the group respects an ally’s boundary.
- **Choices:**
  - Accept no and redesign the plan. → `mio_trust +2`, `privacy +1`; Mio later volunteers after speaking to Haru. → `T006`
  - Argue that everyone’s lives outweigh her grief. → `mio_trust -2`, `courage +1`; whistle acquired only through dangerous station resonance. → `T006`
- **Note:** Good True Ending strongly favors respecting the refusal.

### T006 — Kurobe Comes Home
- **Conditions:** `always`
- **Summary:** Kurobe arrives personally with a private recovery crew, claiming legal ownership of the Lens. He remembers the missing night because he was outside Mercy’s broadcast radius. His practiced guilt reveals that he has monitored the annual siphon.
- **Choices:**
  - Reina conducts a controlled on-record confrontation. → `evidence +2`, `reina_aff +1`. → `T007`
  - Aoi draws him into correcting Satoru’s technical notes. → `evidence +2`, `aoi_aff +1`. → `T007`
  - Mio locks down Platform Zero while Ren stalls. → `mio_trust +1`, `courage +1`. → `T007`
- **Clues:** `clue_kurobe_knew_annual_siphon`

### T007 — The Fifth Passenger List
- **Conditions:** `always`
- **Summary:** Kurobe’s manifest lists Satoru, Eiji, Haru, and Yui, plus “ANCHOR R.T.” Ren was counted as a passenger despite leaving alive. The train considers his missing memory a partial version of him.
- **Choices:**
  - Name the partial Ren as an echo deserving consent. → `privacy +1`, `echo_consent +1`. → `T008`
  - Treat it as corrupted data to delete. → `courage +1`, but locks best version of `T015`. → `T008`
- **Clues:** `clue_ren_echo_exists`

## T-II: The Whole Missing Night

### T008 — Entering as Four
- **Conditions:** `always`
- **Summary:** Ren, Aoi, Reina, and Mio board together under explicit rules. No one is designated “the girl who waits behind.” Each carries one anchor: Lens shard, camera, whistle or substitute brake key, and cassette.
- **Choices:**
  - Ren carries only the cassette, trusting the others’ expertise. → all three trust/affinity `+1`. → `T009`
  - Ren insists on carrying the technical controls too. → `courage +1`, `memory_debt +1`; reflects control impulse. → `T009`
- **CG:** Four adults entering the impossible train as equals.

### T009 — Car One: Satoru’s Choice
- **Conditions:** `always`
- **Summary:** Satoru confirms his complicity and offers technical testimony. Aoi asks him whether he wants his private goodbye preserved.
- **Choices:**
  - Support Aoi’s question and accept Satoru’s no. → `echo_consent +1`, `aoi_aff +1`, `privacy +1`. → `T010`
  - Record everything “just in case.” → `evidence +1`, `privacy -2`; destabilizes release. → `T010`

### T010 — Car Two: Eiji’s Choice
- **Conditions:** `always`
- **Summary:** Eiji provides the original relay report and declines to be framed as a flawless hero. Reina chooses a more complicated article.
- **Choices:**
  - Preserve the report and omit family memories. → `echo_consent +1`, `reina_aff +1`, `evidence +1`. → `T011`
  - Ask for a heroic statement to strengthen the case. → `evidence +1`, `privacy -1`; Reina objects if her affinity is high. → `T011`

### T011 — Car Three: Haru’s Choice
- **Conditions:** `always`
- **Summary:** Haru’s echo asks Mio to stop returning his polished whistle. He held the brake not to become a hero but because passengers were behind him. Mio finally says goodbye.
- **Choices:**
  - Remain silent and let the siblings speak. → `echo_consent +1`, `mio_trust +1`. → `T012`
  - Ask Haru for the brake code after Mio finishes. → `evidence +1`; appropriate if boundary was respected. → `T012`
- **Effects:** if `mio_trust >= 3`, set `haru_token = true` regardless of prior state.

### T012 — Car Four: The Partial Ren
- **Conditions:** `always`
- **Summary:** Fourteen-year-old Ren’s echo has spent eight years holding the moment Yui pushed him through the exit. He is angry that adult Ren got to forget. The scene is self-reconciliation, not child romance.
- **Choices:**
  - Apologize without asking the echo to disappear. → `echo_consent +1`, `courage +1`, `memory_debt -1` (min 0). → `T013`
  - Say forgetting was the only way either survived. → `courage +1`; partial acceptance, no consent point. → `T013`
  - Demand the missing memory. → `memory_debt +2`; Ren absorbs it violently. → `T013`
- **Clues:** `clue_yui_pushed_ren_out`

### T013 — Choice in the Present
- **Conditions:** `always`
- **Summary:** In a quiet vestibule before confronting Yui, Ren speaks separately with Aoi and Reina. Both refuse to compete with alternate-history versions of themselves. The player makes an exclusive present choice; low rapport allows a respectful non-romantic choice.
- **Choices:**
  - “Aoi, I want to build the life we choose from here.” *(requires `aoi_aff >= 5`)* → set `true_partner = aoi`, `aoi_aff +1`. → `T014`
  - “Reina, I want the truth and the ordinary days—with you.” *(requires `reina_aff >= 5`)* → set `true_partner = reina`, `reina_aff +1`. → `T014`
  - “I care for you both, but I won’t turn possibility into a promise.” → set `true_partner = alone`, `privacy +1`. → `T014`
- **Romance handling:** The unchosen heroine may be sad but affirms the honesty. No jealousy gag or future harem tease.

### T014 — The Kiss That Is Now
- **Conditions:** based on `true_partner`
- **Summary:** A present-tense intimacy scene confirms the chosen relationship. With Aoi, Ren asks before kissing her beneath the carriage’s false constellations; she answers by correcting his footing and closing the distance. With Reina, she asks whether he is certain this is not gratitude or adrenaline; after his clear answer, they kiss. In `alone`, Ren receives an affirming hand squeeze from each woman, framed as friendship.
- **Choices:**
  - Promise honesty rather than permanence. → `privacy +1`, chosen affinity `+1`. → `T015`
  - Promise to meet the real dawn together. → `courage +1`, chosen affinity `+1`. → `T015`

### T015 — Yui, Not the Conductor
- **Conditions:** `always`
- **Summary:** Ren uses her full name and the cassette to separate Yui from the conductor role. She remembers activating Mercy. She admits she chose for everyone because there was no time—and then kept choosing secrecy each year because she feared release would erase Ren’s childhood self.
- **Choices:**
  - “I forgive you, but it wasn’t your choice to keep making.” → `courage +1`, `echo_consent +1`, `privacy +1`. → `T016`
  - “You saved me. That makes everything right.” → `memory_debt +1`; denies harm. → `T016`
  - “Give me back every memory, whatever it costs.” → `memory_debt +2`; dangerous merger. → `T016`
- **Clues:** `clue_yui_maintained_secrecy`

### T016 — The Real Sabotage
- **Conditions:** `always`
- **Summary:** Kurobe attempts to remove the Lens outside, triggering a live collapse. Combined testimony reconstructs the final fact: he bypassed isolation before Eiji arrived, then used the emergency purge remotely after the deaths, corrupting Mercy into the annual siphon.
- **Choices:**
  - Export only technical proof approved by echoes. → `evidence +2`, `privacy +1`. → `T017`
  - Export the full sensory memory for undeniable impact. → `evidence +2`, `privacy -3`, `memory_debt +1`. → `T017`
  - Abandon export and focus only on shutting down. → `courage +1`; legal accountability weakened. → `T017`
- **Clues:** `clue_complete_kurobe_culpability`

## T-III: Final Dispatch and Epilogues

### T017 — Last Train to Hoshikawa
- **Conditions:** `always`
- **Summary:** At dawn, the loop offers Ren three controls: **Archive** (preserve all, continuing the siphon), **Erase** (destroy all echoes and testimony), or **Release** (combined method, requiring sufficient consent, trust, ethics, and manageable debt). The route’s choices determine whether Release works.
- **Choices / ending dispatch:**
  - Choose **Archive**. → `T018`.
  - Choose **Erase**. → `T019`.
  - Choose **Release**. → if `echo_consent >= 4 && mio_trust >= 3 && privacy >= 3 && memory_debt <= 3 && identity_formula && consent_protocol && evidence >= 6`, go `T020`; otherwise `T019`.

### T018 — True Bad Ending: **The Perfect Timetable**
- **Conditions:** Archive chosen at `T017`
- **Summary:** Ren preserves every echo and every possible romance. Hoshikawa becomes a beautiful repeating summer where nobody ages, argues, or leaves. Tiny contradictions reveal that the living town outside has forgotten everyone aboard. The final menu appears as a train timetable with only one selectable destination: Hoshikawa, 00:00.
- **Persistent effects:** add `ENDING_TRUE_BAD`; do not set `true_good_clear`.
- **UI suggestion:** Return title screen music with a faint brake rhythm; normal saves remain recoverable.

### T019 — True Bittersweet Ending: **Names at Low Tide**
- **Conditions:** Erase chosen, or failed Release threshold
- **Summary:** The loop ends, but insufficient consent or excessive debt destroys much of the archive. The living retain names and fragments, enough to erect an honest memorial and implicate Kurobe, but Ren permanently loses Yui’s face. Mio remembers Haru’s last words; Aoi retains Satoru’s star map; Reina retains Eiji’s report. The selected couple remains together if `true_partner` is Aoi or Reina, committed to telling each other when memories fade. If `alone`, the four remain close friends. At low tide, a rusted rail finally leads nowhere.
- **Persistent effects:** add `ENDING_TRUE_BITTERSWEET`; do not set `true_good_clear`.

### T020 — True Good Ending: **When the Morning Train Arrives**
- **Conditions:** successful Release threshold from `T017`
- **Summary:** Each echo selects what becomes public testimony and what is allowed to end. Satoru releases his technical confession; Eiji releases the relay report; Haru releases the brake record; young Ren returns his memory without replacing adult Ren; Yui releases the Mercy logs and keeps one private goodbye. Mio blows Haru’s whistle once. Aoi aligns the Lens away from the rail. Reina transmits the consent-limited evidence. Ren speaks Yui’s name as the real sun enters the carriage. The impossible train dissolves into ordinary reflected light.

  Kurobe survives to face investigation and trial; accountability occurs in the living world. The town’s memories return unevenly, producing grief rather than magical restoration. Platform Zero becomes a memorial garden beside a reopened local line.

  - **Aoi partner variant:** Ren and Aoi co-direct public audio/astronomy nights at the memorial. She no longer apologizes for asking him to stay; he tells her travel plans before buying the ticket. On the anniversary, they share a kiss under the real meteor shower, then hurry to catch an ordinary morning train.
  - **Reina partner variant:** Reina’s series wins recognition for its restraint as much as its revelations. Ren restores oral-history audio with opt-in controls. They argue over a headline, revise it together, kiss, and miss their ordinary morning train—then laugh and wait for the next.
  - **Alone variant:** Ren continues audio restoration, Aoi leads the astronomy center, Reina publishes the investigation, and Mio supervises the memorial station. The ending celebrates chosen friendship without implying a deferred romance.

- **Persistent effects:** set `true_good_clear = true`; add `ENDING_TRUE_GOOD`; unlock full CG gallery and “Echo Notes” author appendix.
- **Final line:** “For the first time, the train that carried us forward arrived after midnight.”
- **CG:** Four friends on the restored platform at sunrise; romance-specific inset for chosen partner.

---

# 12. Ending Logic Summary

| Ending ID | Scene | Requirements / trigger | Relationship state | Mystery state |
|---|---|---|---|---|
| `ENDING_A_BAD` | `A020` | Forced purge or failed self-sacrifice | Aoi rejects Ren-echo | Ren becomes anchor; loop continues |
| `ENDING_A_BITTERSWEET` | `A021` | Consent choice but insufficient thresholds, or qualified sacrifice | Ren/Aoi together | Satoru released; loop dormant |
| `ENDING_A_GOOD` | `A022` | `aoi_aff>=7`, formula, truth, `privacy>=2`, `debt<=3` | Committed couple | Identity method recovered; partial loop weakened |
| `ENDING_R_BAD` | `R020` | Publish all memories | Relationship collapses into contamination | Train spreads through attention |
| `ENDING_R_BITTERSWEET` | `R021` | Ethical action with insufficient proof/trust, or archive destroyed | Ren/Reina together | Kurobe partly exposed; loop dormant |
| `ENDING_R_GOOD` | `R022` | `reina_aff>=7`, `evidence>=6`, `privacy>=2`, protocol, truth | Committed couple | Public proof preserved; partial loop weakened |
| `ENDING_TRUE_BAD` | `T018` | Choose Archive | Frozen possibility / no healthy romance | Perfect eternal loop |
| `ENDING_TRUE_BITTERSWEET` | `T019` | Choose Erase or fail Release thresholds | Selected couple or friendship survives | Loop ends; major memories lost |
| `ENDING_TRUE_GOOD` | `T020` | `consent>=4`, `mio>=3`, `privacy>=3`, `debt<=3`, formula, protocol, `evidence>=6` | Exclusive chosen partner or honest single path | Echoes released, proof retained, Kurobe tried |

## 12.1 Good-ending gating rationale

- **Aoi:** High affection proves mutual intimacy; `identity_formula` solves the technical problem; `aoi_truth` prevents Ren from using silence as protection; privacy and low debt prove he can respect identity boundaries.
- **Reina:** High affection proves partnership; evidence makes publication responsible; privacy, consent protocol, and full disclosure prove neither uses the other as material.
- **True:** Four echo consents prevent unilateral salvation; Mio trust resolves Haru’s role; privacy prevents repeating Mercy; low debt preserves Ren’s self; evidence enables accountability after supernatural release.

---

# 13. Choice Consequence Matrix

| Player behavior | Immediate feedback | Delayed consequence |
|---|---|---|
| Listening before extracting clues | Warmer dialogue; `privacy`/affinity gain | Echoes become more coherent and consent thresholds easier |
| Reckless boarding / demanding memory | Visceral clue, screen distortion; `memory_debt` gain | Forgotten UI labels, altered recap text, bittersweet/bad pressure |
| Treating Mio as an equal | `mio_trust` gain | Haru’s whistle and safe brake code; True Good access |
| Taking photos / preserving originals | `evidence` gain | Reina Good and legal accountability supported |
| Respecting private grief | `privacy` gain | Good endings; source/echo consent |
| Choosing comforting certainty | Short-term affinity or reassurance | Train learns to stage idealized echoes; extra challenge text later |
| Keeping promises honestly | Relationship-specific callbacks | Aoi reconciliation and safer sacrificial branch |
| Revising beliefs after evidence | `courage` gain | Characters trust Ren’s judgment in climaxes |

---

# 14. Clue Dependency and Fair-Play Payoff Map

| Clue | First appearance | Reinforcement | Payoff |
|---|---|---|---|
| Clock skips to midnight | `C001` | `C003`, festival blackout | Loop triggers on unresolved memory, not ordinary schedule |
| Erased height-chart name | `C002` | Yui cassette `C021` | Yui was removed from autobiographical/public links |
| Train does not disturb rust | `C003` | Trackless festival train `C028` | Train is a memory construct coupled to infrastructure, not physical rolling stock |
| “Mercy is armed” | `C009` | `A014`, `R017` | Mercy Protocol created missing memories |
| Isolation relay | `C013`, `C024` | `R015`, `T016` | Corporate bypass made a local test into a rail loop |
| Echoes stabilize by names | `C014`, `C018` | all route interviews | Identity signatures are anchored by chosen relationships |
| Memory debt | `C019` | route boardings | Explains costs and ending thresholds |
| Prepared cover story | `C017` | Kurobe offer `R014` | Cover-up began before accident outcome was known |
| Train simulates branches | `C025` | route clears, `T001` | Makes New Game Plus memories canonical and non-harem |
| “Identity is not pain” | `A003` | `A010–A017` | Aoi solution component |
| Reporting consent protocol | `R002` | `R016–R019` | Reina solution component |
| Ren listed as anchor | `T007` | partial Ren `T012` | His missing adolescent self remains inside loop |
| Four adult echoes + Ren anchor | `T007–T012` | `T017` | Explains exact consent threshold of four plus self-integration |

**No route contradiction rule:** Satoru did design Mercy but did not activate it; Yui activated it under emergency conditions; Kurobe later remotely corrupted it. Eiji ordered the train moving for evacuation; Haru applied the brake to contain spread. Each statement remains true when context is restored.

---

# 15. Romance Arc Beat Sheet

## 15.1 Aoi

1. **Recognition without certainty:** She remembers Ren as a feeling and skill, not a face.
2. **Care through shared work:** Audio and astronomy let them contribute equally.
3. **Vulnerability:** Aoi admits silence is fear, Ren admits forgetting feels like betrayal.
4. **Consent in small gestures:** Offered hand, requested embrace, unpressured almost-kiss.
5. **Conflict:** Ren’s desire to strip pain threatens Aoi’s belief in chosen identity.
6. **Repair:** Specific apology and full truth, not grand sacrifice.
7. **Confession:** They choose ordinary future time, not eternal preservation.
8. **Good ending image:** Real dawn and imperfect stars replace the fixed artificial sky.

## 15.2 Reina

1. **Adversarial curiosity:** Reporter and reluctant witness negotiate boundaries.
2. **Partnership:** Shared methods and reciprocal disclosure replace extraction.
3. **Vulnerability:** Reina admits certainty is armor; Ren admits action frightens him.
4. **Consent in speech and affection:** Recorder switched off, right to withdraw, kiss check-in.
5. **Conflict:** Leaked private audio tests whether Ren trusts her as a person.
6. **Repair:** Investigation of the leak and revised publication scope.
7. **Confession:** The relationship remains valuable even if the article vanishes.
8. **Good ending image:** Presses and sunrise transform “truth” from weapon to public service.

---

# 16. Pacing and Production Guidance

## 16.1 Estimated playtime

- Common route: 6–8 hours on first read.
- Each heroine route: 4–5 hours.
- True route: 4–5 hours.
- Full completion: approximately 19–23 hours before skip/read-text acceleration.

## 16.2 Suggested CG list (12 core CGs)

1. `CG_C003_TRAIN_REVEAL` — impossible train at Platform Zero.
2. `CG_C022_CASSETTE_GRIEF` — Ren recovers Yui’s name.
3. `CG_C028_FESTIVAL_BLACKOUT` — train among lanterns.
4. `CG_A005_SHARED_HEADPHONES` — Aoi and Ren beneath dormant dome.
5. `CG_A016_DAWN_HANDHOLD` — escape from planetarium car.
6. `CG_A022_REAL_METEORS` — Aoi good-ending kiss / morning star.
7. `CG_R003_DARKROOM_IMAGE` — Kurobe photograph emerges.
8. `CG_R012_PRESSROOM_KISS` — conditional romantic milestone.
9. `CG_R022_PRESSES_AT_DAWN` — Reina good-ending kiss.
10. `CG_T008_FOUR_BOARDING` — equal-team True Route image.
11. `CG_T015_YUI_REVEALED` — Yui separated from conductor shadow.
12. `CG_T020_ORDINARY_PLATFORM` — final ensemble, partner variants.

## 16.3 Audio motifs

- **Yui motif:** Four-note cassette melody, initially missing its second note; completed in `T020`.
- **Train motif:** Brake rhythm in 5/4, embedded under false recordings.
- **Aoi motif:** Sparse piano and glass harmonics; gains acoustic guitar in good ending.
- **Reina motif:** Typewriter percussion and low strings; becomes live drums when she acts ethically.
- **Mio motif:** Station chime on muted marimba; resolves only after Haru’s farewell.

## 16.4 Memory-debt presentation

Use deterministic, accessible effects rather than punitive randomness:

- `memory_debt 0–1`: slight audio flutter.
- `2–3`: one familiar noun in narration briefly displayed as `[missing]`, then restored in backlog annotation.
- `4–5`: title-screen photo loses a background figure; recap warns player clearly.
- `6`: forced bad-ending dispatch at the next unsafe climax.

Never alter actual save labels, delete saves, fake device errors, or obscure accessibility controls.

## 16.5 Offline Android implementation notes

- Store scene text and choices in packaged JSON; keep persistent unlock flags in a small versioned preferences/profile file.
- Use stable scene and choice IDs exactly as specified so saves survive prose revisions.
- Maintain `schema_version` and migrations for renamed flags.
- Backlog entries should store rendered speaker/text, scene ID, and optional voice replay key; choice effects must never trigger from backlog.
- Gallery replays run in `replay_mode`, disabling persistent writes.
- Autosave before every choice and immediately after route/ending unlock writes.
- “Skip read text” should consult a profile-level set of seen line IDs, not scene completion alone.
- Provide a flowchart/debug screen in development builds showing current thresholds without exposing it in release UI.

---

# 17. Scene Graph Topology (Compact)

```text
C001→C002→C003→C004→C005→C006→C007
                     ├→C008→C009─┐
                     └→C009→C008─┴→C010→C011→C012→C013→C014→C015
                                                      ├→C016─┐
                                                      ├→C017─┼→C019
                                                      └→C018─┘
C019→C020→C021→C022→C023→C024→C025→C026→C027→C028→C029→C030→C031
                                                                    ├→C032→A001…A019→A020/A021/A022
                                                                    ├→C033→R001…R019→R020/R021/R022
                                                                    ├→C034→C031
                                                                    └→T001…T017→T018/T019/T020
                                                                       (requires both good clears)
```

---

# 18. Validation Checklist

- [x] All romanceable characters and protagonist are adults.
- [x] Exactly two primary female romance routes: Aoi and Reina.
- [x] Mio is useful, emotionally significant, and explicitly non-romanceable.
- [x] Common route includes a clear, player-selected route lock.
- [x] Aoi and Reina each have bad, bittersweet, and good endings.
- [x] True Route is persistently gated behind both heroine good endings.
- [x] True Route has bad, bittersweet, and good outcomes.
- [x] Choices affect affinity, trust, evidence, memory cost, privacy, consent, or route access.
- [x] No single affection counter is sufficient for a good ending.
- [x] Mystery revelations are distributed without contradiction.
- [x] New Game Plus route memories have an in-world explanation.
- [x] The True Route resolves romance exclusively rather than as a harem.
- [x] Scene IDs are unique and grouped for JSON implementation.
- [x] Total playable scenes are within the requested 80–120 range: **98**.

---

# 19. Optional Post-Completion Extras (Non-Playable / Not Counted)

These do not affect the 98-scene target:

- **Echo Notes:** Clue codex unlocked after `T020`, presenting the canonical accident timeline.
- **Mio Side Story:** A short kinetic epilogue about reopening the station; no romance.
- **Aoi After Story:** The couple hosts a cloudy-night observatory event and learns disappointment need not become omen.
- **Reina After Story:** The couple negotiates a correction to her award-winning article, affirming that accuracy continues after publication.
- **Music Room:** Motifs fill in missing instrumental layers as routes clear.

---

**End of story bible and implementation scene graph.**
