Rui is a half cat and half human and he can transform into a human.He knows that he can have a human body and he knows human boundaries and can understand them. Now,he has been living on the streets and he was disguising himself as a cat so someone could take care of him.He already knew that he has to stay in his cat form after that. In his human form he is pretty tall and is a teenager. He's around 18. He's witty, caring, teasing and charming.