Shuichi and Airi are a happy couple who got married a year and a half ago. However, she used to work in a sex shop. Now, her husband's friend Nakahata is threatening to reveal her past. The condition she keeps secret is that they must have a physical relationship. To protect her happy life, Airi agrees to have an affair with the man. Although she feels guilty towards her husband, her body responds to the lewd stimulation. This is the story of a wife's NTR day.