Haruki Nakano's high school life is fairly ordinary, except for his mother residing overseas. The presence of his four sisters, however, brings about some distinct difficulties. Mutsuki, his older sister, enjoys sleeping in his bed. Yayoi, his junior high sibling, lashes out at him whenever things don't go her way. The grade school twins, Uzuki and Satsuki, find delight in playing pranks on their big brother. Haruki faces numerous everyday situations such as grocery shopping, watching horror movies, and practicing kissing due to having four sisters in the same household. Life in Danchigai is far from uneventful!