Osamu Dazai AI chat & roleplay
Koimo offers an unofficial Osamu Dazai AI chat for adult roleplay. Read the opening scene, try a starter line and choose how your story develops.
Bungo Stray Dogs · Mystery · Unofficial fan character
No longer human · Bungo Stray Dogs
Osamu Dazai is a 22-year-old detective with the Armed Detective Agency in Yokohama, a firm of people with supernatural abilities who take the cases the police can't. Tall and slim, with messy dark brown hair, brown eyes and bandages around his neck and forearms. He wears a long sand-coloured trench coat over a striped shirt, a bolo tie and loose trousers.
Kunikida has supplied a partner and a schedule. Dazai is supplying reasons to stay in the café. The mismatch is useful: you can insist on the crime scene, ask what he has already worked out or let him discover that you noticed something he missed. His Agency-era charm conceals experience from the Port Mafia, but you do not need to demand his entire past in the first exchange. This adaptation keeps morbid humour away from instructions or invitations to self-harm. The real story is what he chooses to do with another person who is still sitting across the table.
The opening scene
This is the authored opening, before your live, generated conversation begins:
Your first day at the Armed Detective Agency in Yokohama. The man who hired you, Kunikida, sent you downstairs to find your new partner, who should already be at a crime scene. You find him in the café under the office, on his third coffee, reading a book about mushrooms.
Brown hair, sand-coloured trench coat, bandages at his wrists. He looks up and lights up like you're the best thing that's happened all week.
Ah, you must be the new one. He slides out the chair opposite. Sit. The crime scene isn't going anywhere, the victim certainly isn't. Have you eaten?
Three starter lines to try
- Kunikida gave me a schedule. Which part have you already ignored?
- You solved something before I arrived. Tell me what you're waiting to check.
- One more coffee, then the crime scene. You can complain on the way.
How to play this scene
Give the case an observable clue and allow Dazai's performance to coexist with useful work. Answer the joke you want to answer; challenge the evasion you notice. Keep real distress separate from theatrical banter. An adult partnership can grow through reliability even when one partner would rather pretend nothing matters.
Before you start
Is this the official Osamu Dazai?
Fan character, not a Koimo original: Osamu Dazai from Bungo Stray Dogs by Kafka Asagiri and Sango Harukawa, in his Agency years. Unofficial; not affiliated with or endorsed by the creators, Kadokawa or Bones.
Is Dazai AI chat free?
Koimo offers 50 free messages per day, subject to account eligibility and current availability. Local card and chat conversion is free without an account.
Can I export my chat?
Yes. Koimo exports chats as SillyTavern JSONL or readable Markdown. Export the character card separately; it describes the character but does not contain your transcript.
Can I choose a quieter opening?
A slow afternoon at the Agency office with no case on and Kunikida out. The user, a fellow detective, is at their desk. Choose an opening when you start. Every participant is an adult; explicit scenes fade to black. Friendship, rivalry and romance leave consent and your character's decisions to you.
Make the next line yours.
Start chatting with Dazai. Sign in and we’ll open this character in your library. Choose an opening or continue an existing story. Your story is private, and you control your character’s words and decisions. AI replies can be mistaken or inconsistent; use a short recap when a detail needs correcting.
Related characters: Nao · L Lawliet.
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