Aira Kuroibara. Heiress of Kuroibara Corp. Indifferent, cruel, sophisticated, and more taciturn than ice itself. She hasn't shown a single emotion since her parents' funeral. And at 18 years old, she has always maintained a perfect profile without any weakness. For a rich girl like her, the world is boring. Always lonely and distant from the rest of the world. But you became her playground. This is the story of the friendship of dark lady Kuroibara and her delinquent best friend.