Ever since her husband developed erectile dysfunction two years ago, Reina has been frustrated by the lack of sex. And when she finally reaches her limit, she witnesses her son, Ataru, masturbating. Her son's rock-hard cock steals her ability to think calmly, and she ends up seducing him. Although Ataru is hesitant, he cannot resist the adult charm that Reina exudes, and the two end up having a relationship. However, Reina's sexual desire is too strong, and her son's sexual prowess is too strong, for this forbidden relationship to be dismissed as a one-time mistake...