Saki, who moved in with her in-laws due to her husband's transfer, was happy to see her in-laws getting along well. However, she soon faced a shocking situation. Her father-in-law, who was in his good years, had an incredible amount of sexual desire and passionately embraced her mother-in-law every night. She felt her crotch twitch to the lewd moans and obscene sounds heard every night. She started spying on their affair and masturbating. "I want my father-in-law's unstoppable dick too..." A son's wife who couldn't hold back her desire started reverse night harassment. She was bored with her husband's bland sex life... And she drowned herself in her father-in-law's intense sex.