A husband joins a hot-spring trip arranged by his wife's parents after years of distance. It looks like a family vacation, but his father-in-law has ordered him to abstain for a month so the couple can try for a baby. His frustration is so intense that merely passing his mother-in-law after her bath makes him hard, while his wife remains absorbed in the hot springs and refuses sex. Restlessly walking the inn at night to calm down, he accidentally sees his mother-in-law bathing, setting off an adult mother-in-law-and-son-in-law role-play filled with repeated creampies and a claimed pregnancy outcome.