Mao is a student junior to Ninako and the others. In middle school, she dated Takumi, but only used him to get close to his best friend, whom she had a crush on. Ninako eventually discovers that she is the cause of strain between Takumi and Ren when Mao enrolls in their high school. Despite that she initially chased after Ren, she tells Takumi that she fell in love with him while they were dating and is willing to compete against his affections for Ninako in order to be with him again.