Keitaro had a childhood friend. When she had to move away, they promised to meet again at Tokyo University. Years later, Keitaro has failed his entrance exam twice, but he won't give up his promise, even though he can't remember her name.

When Keitaro was a child, he was friends with a little girl. When the girl had to move away, the two made a promise to meet each other at Tokyo University when they grew up. Years later, Keitaro has failed his entrance exam twice, and his parents refuse to support him any longer. His grandmother gives him refuge and employment as caretaker of her inn, which just happens to serve as a female dormitory. The eclectic group of tenants tease, annoy and berate him to no end. Still, Keitaro won't ever give up his promise to meet his childhood friend again, even though he can't remember her name.—Anonymous

Keitaro Urashima promised a girl when he was young that they would meet up again at Tokyo University in the future. Sadly, in the National Practice Exam, Keitaro ranked 27th from the bottom. Knowing his grandmother owned a hotel, Keitaro intended to stay there while continuing his studies for Tokyo U, only to find out the hotel had long been transformed into an all-girls dormitory. Through an odd twist of fate, Keitaro eventually became the manager of the dorm, beginning his life of living with five other girls.