Disillusioned with her mundane daily life, Reiko one day on her way back from shopping accidentally witnesses a shocking scene in a back alley. She sees an unfamiliar married woman being pulled by the hand by a man and dragged into a house. Though filled with shock and fear, Reiko feels deeply stirred inside, her excitement growing uncontrollable. Instinctively, she reaches for her own soft, voluptuous breasts. Her mind tells her to be afraid, but her body burns with heat. That night, back home, she recalls the scene and indulges in intense masturbation. Her curiosity now fully awakened, the next day she finds herself drawn back to the same alley, convinced something hidden lies there. And behind her, a man's shadow slowly draws near...