Two couples who are dissatisfied with each other's sex life are drowning in excitement far from everyday life.Tetsuya's wife, Chaoyang, who is very interested in swapping, proposes to a harmonious couple, Norio and Misato.Even the husbands who could not hide their confusion at first could not suppress their excitement at the appearance of their wives being disturbed by strangers' sticks.Obscene acts that are performed at any time and place escalate beyond the boundaries of the couple.Embarrassment turns into excitement, and desire is insatiable and indulges in pleasure.The two couples who feel new excitement are invited to a new world by "swapping".