Strip The Female Teacher (Onna kyōshi wo hagu)

A couple in their third year of marriage starts noticing trivial things about each other that they didn’t see during their honeymoon phase and frequently argue. They try to overcome these issues, but now they even quarrel in bed. On the other hand, they meet an older couple who have been married for ten years and are still passionate. They shared the excitement of a recent couple-swapping experience with another couple. After learning about the younger couple’s marital concerns, they decide to invite them to their home and suggest couple-swapping.