Mature wife Hitomi Morimoto is having an affair because her husband no longer has sex with her. She wants a child, but that seems impossible without sleeping with him, so she devises a reckless plan to get pregnant by her lover instead. Since both men have type A blood, she assumes her husband will never find out. With that flimsy excuse, Hitomi has unprotected sex and lets her affair partner use her as his plaything.