The Kobayashi family lives in harmony with their daughter-in-law, husband, and father-in-law. However, I was worried that my child would not be blessed. The daughter-in-law who thought that her husband had many siblings and her father-in-law's sperm might be strong asks her father-in-law to seed. At first, she intended to start business, but gradually became absorbed in having sex with her father-in-law. When they found out that they were pregnant, their relationship ended, but after giving birth, they couldn't stand it and they resumed mating again ...