Ataru takes advantage of the weekend to visit his aunt's hot spring inn. His aunt Mai has been running the inn on her own since her husband passed away two years ago. Ataru has always loved his aunt. Going to the hot springs was just an excuse; in reality, he had come to the inn to see his aunt. When he meets his aunt again after a long time, she is still as beautiful and kind as ever. However, that night, Ataru accidentally sees his aunt selling her body to customers...