My stepsister catches me mid-masturbation, her presence unnoticed until she's right behind me. I quickly turn, trying to hide my hard-on, but she's already seen it. Instead of leaving, she asks if she can join, her timidity replaced with a hunger I've never seen before. She strips, revealing her perfect, young body, then straddles me, guiding my thick cock into her tight, wet pussy. She rides me, her big ass bouncing, until I grab her hips, slamming her down onto me, fucking her hard and rough. She squeals, her body convulsing as she squirts, her juices coating us both. I continue to pound into her, her orgasms multiplying until she's a panting, satisfied mess.