Reina Kojima is a third-year senior at En and Hinata's school. She is curently dating Naota Takanashi. A tiger like animal named Rawr sits on her shoulder.
Reina first appears as a background character as one of the seniors teasing Hinata for having a crossdressing boyfriend. She later appears to pretend as the person Naota likes to stop En, who had amnesia, from liking him. Later Reina fell from him and dressed up to try and get Naota's attention but failed. Later Naota returned her feelings and they became a couple.
Naota's father was really against Reina being Naota's girlfriend even without meeting her and sends many people to kidnap her. She pretended to be a geisha along with En to meet to Naota's father. Reina bursted out with anger and blew their cover when Naota's father emphasized Naota not having big earlobes (sign of success for Naota's dad). She pointed out that it's not about the earlobes but about the hard work. Naota's father immediately changed his view about Reina and even told Naota not to let go of her.