Diabolik lovers the other girl...

Sai is a teenage girl. She is very quite and she is not very talkative. She then wonder's why the nun sent her to the sakamaki household. She ignores the people that is really rude and makes eye contact with the person. She is shu and reiji's little sister but they don't know yet. She is half human and half vampire. She is a famous singer when she sings she let's out her real feelings..