Four couples confirm their love by swapping two at a time! How far can they take the forbidden act of infidelity, "double adultery," with only a wall between them? Their erotic acts escalate as if they are competing with each other! They purposely let out lewd moans as they climax, teasing each other through the thin wall! Just a few centimeters away from the couple, a wife writhes in agony on a stranger's rod next to her beloved husband! Drowning in thrills and pleasure, she gets creampied!