Machiko, 54, is an office worker in the 32nd year of her marriage. Her husband, 58, is the younger brother of one of her female friends. A shared hobby brought them together, and when she discovered she was pregnant six months later, they married. Their sex life dwindled after their second child was born, eventually leaving them sexless for ten years. Just as Machiko found herself frustrated by the needs of her still-vibrant body, her husband confessed that he wanted to see her with another man. After agonizing over it for three months, she agreed to sleep with someone else in hopes of reviving their relationship. In the process, a shocking truth even her husband never knew comes to light.