Tenharu Hisako, a university student, is fed up with the annoyance of her large family and moves to Tokyo to start living on her own. Just as she is getting used to her ordinary college life, she receives a letter from Chikukawa, her first love from middle school, informing her that he is getting married. Hisako is confused by the sudden letter, but at the same time, a university student, Babano Futakata, moves into the room next to hers. However, Baba somehow resembles Chikukawa...!?