In the quiet study room, Melanie Marie, the innocent virgin, squirms in her seat as Anthony Pierce, her nerdy step-cousin, tries to teach her. Her eyes linger on his growing bulge, and her mind wanders to forbidden thoughts. Rusty Nails, their milf stepdad, enters, noticing the charged atmosphere. He takes a seat, his eyes roving over Melanie's body, her hard nipples visible through her thin shirt. When Melanie asks about the 'prone bone' in geometry, Rusty can't help but chuckle, seeing an opportunity. He explains it in a way that has Melanie and Anthony blushing, their minds filled with dirty images. Soon, the three of them are locked in a taboo embrace, Rusty's experienced hands guiding the inexperienced Anthony, teaching him how to please Melanie, while Melanie learns the pleasures of being filled by two cocks at once.