Hirai's wife, who lives downstairs from the apartment, has run away from home, and Hirai comes to the Isshiki house to see if there's anything she could be doing. Hirai pours out his worries, but he can't help feeling lonely without his wife and Momoko's kindness, so he pushes her down. Momoko's body, which had been a while since she'd had sex with her husband, is quickly consumed by Hirai, who violates her instincts... The pleasure she hadn't felt in a long time brings out a hidden desire inside her. Before she knows it, Momoko begins to desire Hirai's body herself...