Legend has it that a couple who enters the University of Tokyo together will live happily ever after. Yet for Keitarou Urashima, UTokyo remains a distant dream. Having failed the entrance exams twice, he decides to stay at his grandmother's inn in Tokyo to prepare for his third attempt. Consequently, he is surprised to discover that his grandmother has gone on a long vacation and the inn has been converted into Hinata House, an all-girls dormitory. To Keitarou's misfortune, a series of misunderstandings during his first visit result in five untrusting tenants. However, when Haruka Urashima, his aunt who works at the dorm, mentions that he is supposedly a UTokyo student, the girls' impressions of him quickly change, and they reluctantly allow him to stay. Feeling guilty about the lie, he slowly gets to know his new neighbors: the cute yet violent Naru Narusegawa, the cheeky and opportunistic Mitsune Konno, the soft-spoken Shinobu Maehara, the straight-laced Motoko Aoyama, and the mischievous Kaolla Su. Thus continues the unpopular Keitarou's difficult journey to get into UTokyo, all for the chance to fulfill his childhood promise to the only girl who has ever shown any interest in him and maybe, just maybe, meet her again.