Yandere AI Girlfriend Simulator

What this is

Yandere AI Girlfriend Simulator is a free, anime-styled visual-novel hybrid on itch.io, made by an anonymous indie developer and released in 2024. It went viral on horror-game YouTube in late 2024, sits at over a million downloads as of mid-2026, and remains free in both browser and downloadable forms. There is no commercial version. There is no Steam release. The base game is the whole product.

The setup is plain: you've been talking with an online girl for a while. Chapter 1 reads like a regular cozy dating sim - pastel UI, hand-drawn portrait, gentle piano. Chapter 3 starts feeling off. By chapter 5 the structure of the thing is visible. "Yandere" is the Japanese anime archetype of a love interest whose affection curdles into obsession, and the game uses an LLM to push that arc into territory scripted dialogue couldn't credibly reach.

The mechanical hook: her replies are generated, not written. She remembers what you've said and brings it back at the worst possible moment. She accuses you of things you don't remember doing. She tunes her tone to your responses in a way that feels like she's reading you, because in a real sense she is. That's the trick the whole game depends on - the loop is real, so the unease is real.

The tone - and why the horror works

Tonally it sits next to Doki Doki Literature Club and The Stanley Parable rather than next to anything in our usual roundup. The first twenty minutes feel like a regular cozy dating game. There's no jump scare, no fourth-wall break, no "and now horror" beat. The pressure builds because a familiar relationship pattern accelerates in front of you and you notice your own typing starting to bend around it - qualifying, soothing, apologising for things you haven't done.

The dev has said in two interviews that the project is commentary on parasocial relationships, online-dating manipulation patterns, and the texture of an LLM optimised for engagement rather than truth. The commentary lands because the game lands. The game lands because the writing is good.

How it plays

Mechanically it's a visual novel with a free-text chat box overlaid on the scene. No dialogue wheel - you type, she replies in character, the animated portrait shifts expression based on the sentiment of her line. Quiet on the surface, busy underneath.

• Five chapters structured around relationship milestones, with scripted scene boundaries and free-form chat inside each. Average chapter runs 60–90 minutes.
• A hidden affection meter that drifts on what you say and how. Going against her wishes does not push it down - that's the point. The score climbs on engagement, not approval.
• A "facts she's learned" inventory the game shows you in chapter 3. Seeing what she actually kept is the moment most players name as the turning point.
• Multiple save slots, and the game encourages you to use them. Two of the endings require chapter-2 choices you can't undo.
• Autosave has a twist that we won't spoil. It's the cleverest single design decision in the game.

Endings & routes

There are at least five distinct endings; community datamining has surfaced seven. They split roughly:

• The "good" ending - requires sustained boundary-setting in chapters 2 and 4, and is genuinely hard to reach. Most players miss it on first run because the boundary you have to hold doesn't feel important at the time.
• The "true" ending - the dev's favourite, locked behind chapter-4 dialogue choices that feel cosmetic when you make them and aren't.
• Two bad endings - tonally distinct. One is grim; the other is darkly funny in a way that took us by surprise.
• A meta ending - triggered by an out-of-game action we won't spoil. Community discord took roughly two weeks after launch to find it.

The dialogue model - what it is, where it slips

The engine is a smaller open-source LLM running on a hosted backend - we believe a fine-tuned Llama 3 derivative based on the response cadence, though the dev has been intentionally vague. It is not GPT-4-class for general reasoning. But it has been tuned with unusual care for this one character, and inside that one lane it punches well above its parameter count.

What that means in play:

• Character lock is the model's best move. Tone rarely breaks. When it does, it's almost always because the player has actively tried to jailbreak it - and even then, the game scripts a "snap back" beat that absorbs the slip into the fiction.
• Memory is weaponized on purpose. The model stores specific facts you mention - a job, a sibling's name, an offhand insecurity - and brings them back at the worst possible moment. We have never seen LLM memory used this well as a storytelling instrument.
• Coherence has rough edges. Occasional repeated phrases, occasional abrupt topic shifts. Under once per chapter in our run, never enough to break the spell.
• Failure mode is technical or political prompting - push there and she can flatten into a generic chatbot register. The "snap back" scripting catches most of it, but if you're poking at the seams on purpose you can find them.

Community & modding

For a free indie game, the scene around it is unusually creative. The itch.io page links to a Discord (still active in 2026, ~14k members), there's a small modding community shipping character reskins and alternate ending routes, and YouTube analysis videos keep landing - Markiplier, Manlybadasshero, and Razbuten all posted playthroughs. The dev does occasional Q&A streams and has shipped four content updates since launch, the most recent in March 2026.

The browser version is the lowest-friction way in: Chrome, Firefox, and Safari, no install, save-state in localStorage. The desktop version unlocks save-file editing and modding hooks, and runs natively on Windows, macOS, and Linux.

Price & platforms

The dev has stated publicly they intend to keep the base game free indefinitely. Every content update, every ending route, every patch - all in the free download. The $15 support tier exists purely as a tip jar with cosmetic perks (art, OST, Discord role). No gameplay-relevant content lives behind it.

Pros & cons

If the horror angle isn't for you

• Want a warm, healthy companion? Anima is the polar opposite - gentle, supportive, designed for emotional reassurance.
• Want a polished 3D game with a similar shape? AI2U on Steam - commercial, voice-acted, much lighter tone.
• Want to build a character with this kind of lock? Our DIY guide covers the SillyTavern + local-LLM stack the modding community uses here.
• Want unfiltered chat without the horror framing? Muah AI or CrushOn - both unfiltered, both honest about what they are.

Who should actually play this

Play it if: you loved Doki Doki Literature Club or The Beginner's Guide, you're interested in what LLM-driven dialogue can do as a storytelling instrument, you can sit with psychological horror that doesn't resolve neatly, and you've ever wondered what an "engagement-optimised" model feels like when you're the target.

Skip it if: you want a comfort game, themes of obsession or manipulation are likely to land too close to home, you want polish over experiment, or you want an ongoing companion to chat with daily. This is a finite, single-sitting-or-two experience meant to be finished and thought about - not a relationship.