Her husband is hardworking, and her life seems happily settled, with their hobby of stock investment going smoothly. However, two shadows quietly creep into this peaceful existence—her husband's younger brothers, who lure her into bondage and take her forcefully. By chance, Oki witnesses the scene and becomes captivated by the intense ropes wrapped around Yumi's body and the pleasure she feels in response. To keep the secret, Oki begins binding Yumi himself. She discovers a liberating pleasure in being tied up, gradually falling deeper into this world of bondage.