The problem child of the Supplementary Lesson Department. Despite her appearance, she's a student who only says naughty things when she talks. She has a huge risqué behavior, doing things like attending classes in her swimsuit and having almost every word escape her mouth be a double entendre, which makes everyone uneasy around her. She is love teasing sensei in the pervert way and actually hanako is a pervert that craving for do naughty things.