Index

A large language model without a face is infrastructure. When bilibili finished training Index, the question became how people would live with it. The interface was stripped back so the model's character could surface through conversation rather than decoration. The character creation system made users into authors — defining not just appearance but behavioral characteristics that shape how their AI companions respond. Sharing was designed as a core loop, not an afterthought, recognizing that AI companions gain meaning through social context. The result is a product where technology recedes and relationship becomes the interface.