An ordinary couple's daily life takes a sudden turn. Six months ago, they received a call from the husband's junior colleague, Yokoyama, who was usually cheerful and energetic but now seemed deeply depressed. Seeing his condition, the couple decided to invite him over to their home. However, this single act becomes the turning point of their story. Yokoyama's presence brings an unexpected twist, foreshadowing a disappointing turn of events. The couple's life plunges into a new drama—centered around betrayal, desire, and forbidden passion.