She is a cute, yet strong-willed young wife who is caring for her husband every day. She would never cheat on him. One day, a man pushes her down, hoping to get close to him, but she refuses him with all her might. In the midst of her resistance, her eyes are captured by a huge cock. The firmness of the cock is so great that it shakes Kokoro, and the moment it is inserted, the cute young wife stops being human. She becomes obsessed with the other man's cock, and becomes a pervert who repeatedly has sex while constantly yelling about how it is different from her husband's cock.