Shizuku

Shizuku is a Mizuchi (Water dragon demon) in the form of a green, short-haired small girl with snake tongue that can stretch rather far, similar to that of a chameleon, and can breath underwater. Shizuku usually has a stoic expression, and is almost always completely soaked with water. She first meets Yūto at a river, where she warns Yūto that if he continues to go along with his demon slayer heritage, she would kill him. To make sure of this she invites herself to live in Yuto's house and starts to like him romantically.