On their fifth wedding anniversary, the Shiomi couple went to a high-class restaurant. There, Yuriko, the wife, received a discount ticket for a massage from an employee. Yuriko immediately visited the massage parlor at her husband's urging. At first, she was relaxed by the treatment using oil, but the masseuse's fingertips gradually approached her groin joints and her anus, and, being told that it was a medical procedure, she was unable to resist and ended up having her anus penetrated. Since then, Yuriko has not been satisfied by vaginal intercourse with her husband, so she visits the massage parlor again...