kinshin soya, the son of satsuki's daughter, satsuki shibaoka.

With her husband's sexlessness, she becomes frustrated and jealous when she sees her son's cock in the morning. Since then, Satsuki, who was unable to control his desires, began to attack him in the bath and sleep, and he became more proactively repeating a misconduct against his son. And my son gradually became sexually jealous of the pleasure given by Saki.