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BunCho

ALL-IN-ONE MULTIMODAL AI STORY STUDIO

웹소설, 32페이지 풀컬러 만화, 2.39:1 실사 영화, 90초 애니 OP를 하나의 바이블로

《킬러는 결말을 모른다》(16컷 시네마스코프 영화)와 《마지막 마법사는 잠들지 못한다》(90초 보컬 애니 OP)를 만든 바로 그 프로덕션 파이프라인을 무료로 시작하세요.

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Good to know: The studio's interface is available in English, Español, Português and 繁體中文 (choose it in Settings), and plans are billed in US dollars. The account sign-up and login pages are still in Japanese.

The studio's writing screen: a chapter and section tree on the left, the manuscript in the center, and the AI chat on the right with rewrite and brainstorm modes and a model picker
The actual writing screen: chapters on the left, manuscript in the middle, AI chat on the right.

How it works, in five steps

Follow these steps in order and you'll be writing within minutes. Any change the AI proposes stays out of your manuscript until you press apply.

  1. Create a work

    Give your project a title. Works in progress and finished works are kept on separate tabs.

  2. Add chapters and sections

    Build the outline in the chapter panel and write in the center. Splitting a long novel into sections keeps every scene easy to find and revise.

  3. Brainstorm with the AI

    Switch the chat to brainstorm mode to talk through plot holes, character motives or what happens next. Point it at a chapter, a character sheet or your world notes with @-mentions.

  4. Rewrite with a diff

    Select a passage and say what you want — more atmosphere, more dialogue, third person, tighter pacing. Deletions and additions are highlighted; apply or discard.

  5. Revise many chapters at once

    Ask the agent for a sweeping change, such as making one character speak formally across chapters 2–4. It shows a plan and a cost estimate first, then a per-section diff you can accept piece by piece. A checkpoint lets you undo the whole run.

What the studio does

The Cursor for stories

Cursor is a tool programmers use to write code with AI. AI BunCho is the same idea for storytellers: write your story with AI, then turn it into comics, videos, songs and games.

Brainstorm and rewrite modes

Discuss ideas in brainstorm mode; edit prose in rewrite mode, always with a before/after diff.

Version history and checkpoints

Each accepted change saves a version. Roll back a single edit or restore the whole work to the moment before an agent run.

Choose your model

Pick from current models such as GPT-6.1 Sol and GPT-6 Luna. Lighter models handle tab completion to save credits.

Editing ideas borrowed from code editors

Tab completion suggests the next few sentences in faint text; inline edit (⌘K, or "Fix with AI" on phones) rewrites a selection in place; Ask, Plan and Agent modes handle bigger revisions.

Writing rules per work

Set point of view, style, banned words and how each character talks. Every AI request follows them.

Titles, synopses and export

Generate title and synopsis candidates from your manuscript, then export in a format that pastes cleanly into Shōsetsuka ni Narō and Kakuyomu.

Works on your phone

It runs in the browser, so there is nothing to install. Draft a section on the train and polish it on your laptop.

Comics, video and music from the same work

Turn a chapter into a four-panel comic, page manga or webtoon; build a storyboard and animate the cuts; write lyrics and make a song or music video. Add, reorder and edit dialogue on each storyboard card, fix a cut by describing the change, and swap faces, lyrics or voices in a finished video.

Key visuals, posters and ads (all paid plans)

Make key visuals, posters and promos from your story, or ad campaigns for a product: three plan options with the reasons behind each technique, a design editor with 69 media sizes (Meta, Google, TikTok, LINE, X, print with 300 dpi bleed and trim marks), brand kits, bulk variations, preflight checks (legal wording checks are hints, not legal advice), a comment-only review link for clients and ZIP delivery.

Studio vs. the free BunCho tools

Free BunCho toolsStudio
PriceFree, as alwaysIncluded in paid plans (7-day free trial for first-timers)
What it doesTitle generator, synopsis generator, AI relay novelLong-form drafting, brainstorming, rewriting, multi-chapter revision, export
WorkspaceOne screen per toolChapter tree + manuscript + AI chat on one screen
AI modelsBunCho's own Japanese modelCurrent models such as GPT-6.1 Sol and GPT-6 Luna
EditingPick from generated optionsFree-form instructions, review the diff, then apply
History—Version history, restore and checkpoints

Plans

Four plans include Studio. First-time subscribers get 7 days free with 500 trial credits and 1 video (up to 30 s).

Watering (水やり)

US$9.99/month

JPY plans are also available from ¥1,500/month before tax; credits vary by billing currency.

  • Studio access
  • 2,250 monthly AI credits (USD billing)
  • All existing paid features

Best for ongoing novels

Seed (シード)

US$19.99/month

JPY plans are also available from ¥3,000/month before tax; credits vary by billing currency.

  • Studio access
  • 5,000 monthly AI credits (USD billing)
  • For writers adding chapters every month

Feast (焼肉)

US$34.99/month

JPY plans are also available from ¥5,000/month before tax; credits vary by billing currency.

  • Studio access
  • 10,500 monthly AI credits (USD billing)
  • Own-GPU generation is unlimited (fair-use limits apply)
  • For heavy multi-chapter agent revisions

Full Course (フルコース)

US$199.99/month

JPY plans are also available from ¥30,000/month before tax; credits vary by billing currency.

  • Studio access
  • 70,000 monthly AI credits (USD billing)
  • Own-GPU generation is unlimited (fair-use limits apply)
  • For larger writing and video projects

Unused monthly credits roll over for up to 3 months, up to 2× your monthly amount (older credits are used first; trial credits don't roll over). Credits are an estimate: how fast they go depends on the length of your work and the model you choose. If you run out, you can opt in to capped pay-as-you-go or buy a prepaid credit pack. Nothing extra is charged without your consent. Cancel anytime from the studio settings; cancel during the trial and you pay nothing. Credit packs can also be paid with Alipay or WeChat Pay (charged in JPY) when the studio is set to Japanese or Traditional Chinese. On Feast, Full Course and Team, images, songs, voices and LTX video made on our own GPUs use 0 credits (fair use: e.g. 300 images, 120 s of video and 30 songs a day; hosted models still use credits, and nothing switches to paid automatically). AI video now costs 6.6 credits per second on our own GPUs, 13.2 for hosted economy and 26.4 for standard.

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Frequently asked questions

Is the studio free?
The studio is part of the paid plans (Watering, Seed, Feast and Full Course). First-time subscribers can try it free for 7 days. The title generator, synopsis generator and AI relay novel remain free.
Will the AI change my manuscript on its own?
No. Rewrite mode, inline edit and the agent all show a before/after diff first. Your text changes only when you press apply, and each accepted change is saved as a version you can restore.
Which AI models can I use?
Current models such as GPT-6.1 Sol and GPT-6 Luna, chosen per task. Light tasks like tab completion use a lighter model. Different models use credits at different rates.
What happens when I run out of AI credits?
The editor warns you when you're running low. To keep going, you can opt in to pay-as-you-go with a monthly cap or add a prepaid credit pack. Without your consent, there are no extra charges.
What happens to credits I don't use?
Unused monthly credits roll over at each renewal and stay usable until the end of the third month after the month they were granted. The rolled-over balance is capped at 2× your plan's monthly credits; anything above that expires, oldest first. Older credits are always used first. You can see rolled-over credits and their expiry dates in the studio's usage meter, and rollover/expiry entries in Settings → History. Trial credits don't roll over. If you move to a smaller plan, rolled-over credits are capped at 2× the new plan. If you cancel, they end with your current billing period. Purchased credit packs never expire.
Can I post what I write to Narō or Kakuyomu?
The export function formats your text for both sites. Each site has its own rules on AI-assisted works (such as disclosure), and they can change — check the latest guidelines before posting.
Is the interface available in my language?
Yes. Open Settings in the studio and choose English, Español, Português or 繁體中文. A few newer screens, such as the voice comic editor, are still Japanese only.
How do I cancel?
From Payments & cancellation in the studio settings, anytime. You keep access until the next renewal date. Cancel during the free trial and you won't be charged.
What does “unlimited own-GPU generation” mean?
On Feast, Full Course and Team (not during the free trial), images, 4-panel comics, manga panels, character sheets, songs, voices, LTX video, upscaling and cutouts made on BunCho's own GPUs use no credits. Fair-use limits are 300 images, 120 seconds of video and 30 songs a day (3,000 images, 1,200 seconds and 300 songs a month). When the GPUs are busy these jobs run after paid jobs. At the limit you can choose a hosted model (uses credits) or wait for the next day; nothing switches to paid automatically.
Can I use what I make commercially?
Yes. Text, images, comics, video, voices and music made in BunCho can be used commercially. Rights in material you bring in, real people or existing characters stay with their owners, and voice credits such as VOICEVOX must be shown as their terms require.
Are there hourly or weekly usage limits?
No. You can use your monthly credits whenever you like within the month. When they run out, you can opt in to capped pay-as-you-go or buy a credit pack. On Feast, Full Course and Team, unlimited own-GPU generation has daily and monthly fair-use limits.
Can I make ads and banners?
On every paid plan (Watering, Seed, Feast, Full Course, Team) you get ad campaigns, the design editor, brand kits, product data, bulk creation, preflight checks and ZIP delivery. For companies, see the team page at /studio/business or contact us via /studio/enterprise?lang=en (pricing on request).

Your next novel, finished with AI.

Outline, brainstorm, rewrite and export — all on one screen.

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