One day, Hikari, who is troubled by the lack of sex between her husband and her husband, suggests that she register for a ``couple exchange club.'' She vehemently opposes a suspicious organization that she is not used to hearing about, but her husband persuades her and gives in. I immediately decided to have sex with a certain couple. At first, Hikari refuses, but she gets hooked on the pleasure that her husband can't feel... A defeated, lewd housewife drowns in sex.