Rosalyn Sphinx has the best stepmom ever. After class one day, her stepmom informs her that shes been helping her stepbrother with a particular problem, but she needs some help. Turns out, their stepmom has been helping him jerk off. She enlists Rosalyns help in tutoring her stepbrother and introducing him to all the pleasures of pussy. They open his bedroom and barge in on him jerking off. Rosalyn wastes no time taking his dick in her mouth and sucking him off while stepmom watches approvingly. The next day, Rosalyn is talking to her stepmom over lunch when her step bro wanders into the kitchen. His eyes fix on his ass, peeking out from under the pale pink slip shes wearing. Like a magnet, his stiff cock pulls him closer to her ass. Shes happy to see him and even happier when he lifts her slip, exposes her ass and slides her panties down around her ankles. He fucks her from behind, all the while their stepmom sitting there watching them fuck.