42-year-old married woman Sayoko has an abnormal fetish—she prefers rimming men over eating three meals a day. With a seductive and perverted appearance, she becomes obsessed with men's anuses, frantically licking and performing rimjobs, even inserting her tongue deep inside the anus with vigorous tongue thrusts, chasing extreme pleasure. In stark contrast to her ordinary life as a wife, her hidden desires are deeply engraved upon her body and mind.