The main character of the story, Haine is the fifteen year-old bodyguard of the student council president. She is known for not being very bright, but she has a good heart. Her Yankee name was "Seashore Cinderella".

Haine was born to the Kamiya family but was adopted into the Otomiya family when she was 10 years old for 50 million yen. At that time Haine believed it was because her father Kazuhito despised her for not being a good enough heir. Haine is able to reconcile with her father after realizing that Kazuhito had always loved her as his daughter and only wanted her to be happy.