Ayumi is married to a man much older than her. They were very close at first, but after three years her husband's cold attitude started to become more noticeable... She talks with her husband and things calm down for a while, but she can't stand his repeated affairs and runs away from home. After some hesitation, Ayumi consults with her husband's friend, Ozawa, and is Kokoro by his kind attitude, and they end up having sex. The two steadily grow closer. But such an unfaithful relationship can't last long...