One night, Kenji is invited by his friend Yukio to his house, saying, "I'll show you something good." There, he witnesses Yukio's beautiful stepmother indulging in masturbation. The stepmother writhes her voluptuous body and ascends to heaven. Then her son comes in and witnesses the shocking sight of them devouring each other's genitals and engaging in even more lewd acts. Kenji is tempted by the lewd behavior of his beautiful stepmother, which remains in his mind, and he returns to his house to press in. The beautiful stepmother reveals her lewdness and opens her pussy, asking for intercourse.