The Miyahara family lives harmoniously with the wife, husband, and father-in-law. However, they are troubled by their inability to have children and consult the father-in-law. Although the father-in-law also couldn't find an answer, the wife thought that perhaps her husband's brothers were numerous because of her father-in-law's strong sperm, so she asked him for artificial insemination. What started as a business-like arrangement gradually turned into an obsession with sex with her father-in-law. They agreed to end their relationship once a baby was conceived, and when the pregnancy was confirmed, their relationship ended. But after giving birth, they could no longer hold back and resumed artificial insemination intercourse...
