Airi, who lives modestly in a housing complex with her doctor husband, one day catches him in the act of cheating. By his side is a married woman from the same complex... so, he was having an affair with another man's wife. When she consults with the other man's husband, Tanaka, he doesn't believe her, so the two decide to spy on the moment of infidelity together. After witnessing the decisive moment and feeling hurt, the two draw closer to each other to fill their loneliness. The two, whose life partners have been stolen, run towards an affair with each other due to their unfulfilled hearts...
