Yui was born mute and so she never had a lot of friends, and is insecure. She is a girl with brown hair and blue eyes, she is very pretty, but people tend to just look at her and not approach her. She is shy and awkward. She wants to have friends but never approaches firsts. Yui can only make noises through her mouth, like "mmmh" or "ghh", and can't even say one full word. She is very smart at school and diligent.