A little south of the mainland, there is an isolated island covered by gentle slopes. Climbing up the stone steps leading up from the base of the island, one can see the town and the sea from the summit. On that hill, there is a school which the protagonist, Hoshino Wataru, attends. On another hill nearby stands the old school building that was refurbished into a dormitory. However, the company whose factory made up a large portion of the island's industry decides to shut down its operations. As a direct result, the number of students is decreasing. The lack of attending students only leaves Wataru and a few girls, mischievously called his harem, living at the dorm. Together with a new student transferring in during this unlikely period, they try to enjoy carefree days, before they inevitably have to part ways.