Aina is a bright, cheerful, and flirtatious girl who often teases and provokes her homeroom teacher Tanaka-sensei, who she calls Tanakacchi. She correctly ascertains that her teacher is a virgin, and offers to 'pop his cherry'. She tells Tanaka that it's her first time while performing oral (something which he doesn't believe), and this is revealed to be true when they have sex shortly after.