The story centers on Yoko, a woman who has never had a boyfriend before. She signs up on a dating app, where she meets a salaryman named Fumiyuki Kamisu. Yoko starts dating Fumiyuki, without knowing that he is actually married. Fumiyuki later tells Yoko that his wife, Rei, found out about their affair, and even asks to meet her. When Yoko meets Rei to apologize, instead of accepting her apology, Rei asks Yoko to continue her affair with Fumiyuki.