Koushi Nagumo, a 12-year-old boy, faces an unexpected turn of events when his father leaves him alone after their house burns to the ground. Koushi is left to manage on his own and collapses on the streets. Fortunately, he is rescued by a quirky woman named Mineru Wachi, who takes him to the all-female dormitory Megami-ryou. Mineru, who is the temporary manager of Megami-ryou, feels sympathetic towards Koushi's situation and invites him to become the official dormitory mother. However, Koushi finds himself dealing with a bunch of residents with their unique and bizarre quirks. These include Atena Saotome, who is fearful of men but exhibits a kind nature, Kiriya Senshou, who appears masculine but is quite feminine, and Mineru, who is passionate about science and often gets into trouble with her reckless experiments. Despite the unusual circumstances, Koushi works hard to fulfill his role as the dormitory mother and navigate through his crazy new life.