After a long time, a couple went on a trip alone. They visited a very cheap inn in a hot spring area. The moment they arrived in their room, they heard a woman's intense panting. It seems the walls were too thin, and the sounds from the next room were leaking through... Hearing that sound, the wife secretly becomes aroused. And the husband plans a swapping. They start exchanging wives and begin to sleep with each other's spouses. The couple cheats on each other across the thin wall of just a few centimeters. The sense of immorality transmits and increases the pleasure. In the end, they irresponsibly ejaculate heavily inside someone else's wife...