Two couples, a boss and a subordinate from the same company, came to a hot spring inn. The boss, who is a regular in the posting magazine and is a swap maniac, ordered his subordinates to participate in the couple exchange trip. As soon as I arrived at the inn, my boss contacted me to come to the open-air bath. An anxious subordinate's wife, Naoko. However, the husband tries to establish his future status by sharing secrets with the managing director of a large company. When I persuaded my reluctant wife to go to the open-air bath, my boss's wife, Mitsuko, was being photographed for posting. Naoko can't stand the stupidity and runs away. A husband who is guided by Mitsuko and participates. That was the beginning of a couple's sexual intercourse that goes crazy with sexual desire...!