At age twenty, Keitarou Urashima, after failing the Tokyo University entrance exam twice, feels disheartened about his future. Hoping to refocus on his studies, he receives a call from his grandmother, who manages a traditional inn, suggesting he move there. However, upon arrival, Keitarou discovers the building has transformed into an all-girls dormitory, housing five unique residents: Naru Narusegawa, a studious girl also aspiring to attend Tokyo University; Mitsune Konno, a free-spirited freelance writer; Kaolla Su, an enthusiastic inventor; Shinobu Maehara, a quiet girl searching for her place; and Motoko Aoyama, a dedicated kendo practitioner.
Initially met with skepticism, Keitarou eventually becomes the dorm’s manager and gradually forms bonds with each girl while still holding onto his childhood dream of entering Tokyo University alongside a special girl from his past.