8-year old Yotaro gains a 3-year old step-sister, Kaoru, when his mother marries a jazz musician who plays in a club in Naha, Okinawa where they live. Before long Kaoru's father deserts them, and not long afterward Yota's mother becomes terminally ill. Her dying wish is for him to watch out for Kaoru at his grandmother's place on a small island off the coast of Okinaw...