The Matsumoto couple have continued regular baby-making sex after marriage. However, they have not been blessed with children, and even after visiting the hospital together, no clear cause was found. The doctor suggested the husband's sexual performance might be the issue, increasing their anxiety. Invited by the neighborhood association chairman to a meeting, Riho is gradually seduced under the guise of infertility treatment. The unfamiliar pleasure and excitement, absent from her routine marital relationship, begin to shake her mind and body.