Yū Akahane moves to a dormitory room after her father's transfer at work. She and Haruto, aka "Black Devil", have the worst meeting. Since then, Haruto treats her like his slave. The only person who is kind to her is Takumi, aka "White Prince". Haruto orders Yū to go to her middle-school reunion, but Yū, who doesn't want to remember her middle school days, refuses. At this time, Suzune appears. She is a childhood friend of both Haruto and Takumi. Due to her, the relationship between Yū, Haruto and Takumi changes.