Kenji and his mother Ayumi, who live together in a single-parent household, are visited by their mother's younger sister Kana. In the past, Kana would often play with them and take baths with them, and Kenji was excited to see that his aunt, who had come back after a long time, was as beautiful as ever. That night, when Kenji was taking a bath, his aunt came in and said, "I'll wash your body," just like in the old days.