That scene is burned into his mind and won't go away. No matter how many times he cums, the rising passion never subsides. Not knowing how to deal with the excitement he's never felt before, Sato indulges in masturbation. The scene that drove Sato crazy was the defenseless naked body of his mother Riku while she was taking a bath. Her breasts were dripping wet. At the moment he witnessed it, something inside Sato broke, and Riku's existence changed from a kind mother to a sexual object. He wants to see his mother's breasts again. He wants to touch them, he wants to suck them... Driven by intense emotions, Sato breaks into the bedroom where Riku is sleeping.