Kenta was struggling on his own after seeing off his wife who was in her final month of pregnancy and going back to her hometown. He felt lonely, but he had to do his best for the sake of his unborn child. Then suddenly, his sister-in-law Fumina came to check on him. "Since you've come all the way here, let me help you with the housework," Fumina offered, and Kenta's loneliness was eased. However, Fumina was always close to him no matter what he did, and he gradually lost his sense of reason. (I have a precious family...) He knew that in his head, but he couldn't resist the temptation of her beautiful breasts and body...