Koji has lost his parents and will live with his brother and his wife. Rieko, her brother-in-law, is dissatisfied with her husband's night life with Koichi. Such a Futari opens the forbidden door with a strange kick ... The cock that warped against Koji's gingin pushed the switch of Rieko's desire. Slender body, attractive lips ... Can Rieko end that day as a one-time mistake?