Mother Anna who lives with her two sons Takahiko and Shuji. On the surface, they had a happy family life, but Anna and her eldest son, Takahiko, had a secret. It had a physical relationship while being a parent and child. The fact that they were once separated due to family circumstances has instead brought them closer together. However, by chance, the second son, Shuji, sees it. Shuji suddenly becomes aloof and tries to keep a distance from the two of them, but Takahiko wants Anna even more because he's so lucky...