The first volume in a definitive eight-part collection tracing Japan's couple-swapping and orgy scene from the Heisei era into Reiwa. It includes rare group-sex footage shot 40 to 50 years ago, young adult couples trying an orgy in a voyeur room near Kabukicho, rural nighttime wife-sharing that continues in Shikoku, an orgy-loving couple enticing a faithful big-tit wife and her husband, and mature couples joining sex parties to improve their love lives.