Chiaki Niimura is 34 years old. She married her husband after six years of passionate love, and including the time they lived together, they have been together for 14 years. It's not that she has grown to dislike him, but before she knew it, they had become like air to each other... What bothers Chiaki even more is the constant moans of her mother-in-law that she hears from downstairs in the middle of the night. (Even her mother-in-law, who is almost 60 years old, is able to please her as a woman...) Now that Chiaki feels too embarrassed to do it with her husband, it was inevitable that she would start seeking pleasure outside, and recently she has been keeping five or six "convenient male friends" that she met on dating sites.