Surrounded by her husband's kindness, Mitsuki Hoshikawa lives a seemingly happy daily life. Yet she is secretly having an affair with her acquaintance, Kyohei, who is also married. After seeing her husband off to work, Kyohei arrives at her home—both of them bound by marriage to others. They try to forget about each other's spouses, but every reminder of her husband's love and Kyohei's wife stabs at her conscience, making Mitsuki silently resolve, "I have to end this." However, the more she thinks of breaking it off, the more her body trembles in response to Kyohei's desire, filling with overwhelming lust. A heartbreaking tale of infidelity where love and desire painfully intertwine.