After giving birth to his daughter-in-law, Ryota decided to live alone for the first time in a long time. Ryota, who felt lonely in an empty room, welcomes his sister-in-law, Rena, who suddenly came. However, Rena's real purpose was cheating sex. - A demonic hand creeps up on Ryota, who enjoys bathing without knowing it. - While smiling at Rena's beautiful face, her reason is blown away by her fleshy and glossy body.