Shoichi Yamaguchi has a stepwife named Tomoko. This Tomoko is an unusually lewd woman who desires nightly activities, but Shoichi has not been able to satisfy her for the past year. The reason is that the company's situation is not good, and he is exhausted from working hard every day. At such a time, Shoichi accidentally witnesses Tomoko engaging in self-pleasure. As a husband, Shoichi is driven by self-reproach, but an idea flashes through his mind. It was the idea of letting another man embrace his wife.
