Shimana Kameko has been miserable at home since her mother's death and her father's remarriage, so one morning she runs off and ends up tripping over a man asleep in a park. The stranger, Taiga Fujiwara, offers her a room on three conditions: that she explain why she ran away, that she recover his lost key, and that she have a dream. Shimana takes the deal and moves in, sharing the place with two other young men, her classmate Zen Nakajou and the older Asahi Tatsugae.