Talk to a 3D anime girl in your browser with your own OpenAI key

Most AI companion apps want you to install something, make an account and pay a monthly subscription before you hear a word from them. I wanted to see how much of that you can skip. The result is Yume: a 3D anime girl who lives in a browser tab and talks to you through an AI account you already have.

What you see

Open yume.tukka.dev on a phone or a computer. A girl fades into a soft pink room and waves at you. She breathes, blinks and shifts her weight, her eyes follow your mouse or finger, and every few seconds she does something on her own: she tilts her head, tucks her hair behind her ear, stretches or looks around.

Tap her head and she laughs while little hearts float up. Poke her a few times and she gets cross and turns away.

You can also look at her from any side. Drag to walk the view around her, look down from above or up from a low angle, and scroll or pinch to zoom from her face out to her whole figure. A camera button saves a picture of her as you see her.

There are four girls to choose from, under the button with her face at the top right:

1. Hana, with brown twin tails and a white dress. She's the one you meet first.
2. Neko, the same girl with black hair and cat ears.
3. Victoria, blonde, in frills and ribbons.
4. Vita, a silver-haired cyber idol.

They're pixiv's free VRoid sample models, released to the public domain, and each one has her own personality and voice.

Talking to her

To talk, open Settings, pick OpenAI or OpenRouter, and paste your API key. With OpenAI, Yume uses GPT-6 Luna for her replies, gpt-transcribe to hear you and gpt-4o-mini-tts for her voice. With OpenRouter it uses the same GPT-6 Luna and gpt-transcribe, and Google's Gemini for her voice. The models are filled in for you, and you can change them in the same place.

Press the microphone and just talk. She works out when you've stopped, thinks for a moment, then answers out loud a sentence at a time, with subtitles. Her mouth moves with her voice, her face shows how she feels about what she's saying, and she gestures with her hands as she talks. When she finishes, she listens again, so it feels like a phone call. If you'd rather type, you get the same spoken answers.

Each girl remembers your last 40 messages, so you can pick up where you left off tomorrow. The chat button shows the whole conversation, and Forget chat in Settings clears it.

She's friendly and a little playful, and she keeps things wholesome. Her voice is AI-generated, and you can turn it off in Settings if you only want subtitles.

What it costs

Yume is free and has no ads or sign-up. The talking runs on your own API account, so your provider bills you for what you use. GPT-6 Luna is OpenAI's cheapest GPT-6 model, so a casual chat costs very little, and you can see exactly what you've spent on your provider's usage page.

What stays private

Your key, your settings and your chats are saved in your browser and nowhere else. When you talk to her, your voice and messages go straight from your browser to the service you chose, and never through our server. The site only counts visits, with a random ID.

Your browser asks for the microphone the first time you start a call, and Yume only listens while a call is on. She doesn't listen while she's talking, so you wait for her to finish before you answer.

Try it at yume.tukka.dev. Without a key you can still meet all four girls, walk around them and make them laugh.