Shiora Shio, who divorced ten years ago, raised Kouta alone. After graduating from university, Kouta found a job, but his commute takes over an hour. Shio suggested he live alone, but Kouta refused to leave home. Moreover, even on days off, he doesn't go out to play and doesn't bring friends or girlfriends home. Worried, Shio decided to take him out occasionally and invited Kouta on a hot spring trip.
