"Stepmom, I can't take it anymore." Rin had been having a physical relationship with her stepson, Yuya. It was supposed to be a one-time affair. However, Yuya, who was in the midst of adolescence, could not forget the pleasure of sex and began to assault Rin almost every day. Fearing that the family would fall apart, Rin tried to dissuade Yuya, but... Yuya's sexual desire grew even stronger, to the point where he would get an erection the moment her husband left the house. Before she knew it, Rin's body also succumbed to the pleasure...