Mijn nerdy stiefzus laat me een paar van de smerige dingen zien die ze heeft geleerd uit een erotisch boek

I'm not good at school, and with this big test coming up, I'm going to be totally fucked if my nerdy stepsister Sera Ryder doesn't help me out. But when the stubborn girl won't budge, I steal her glasses to make her pay! The only way I'm giving them back is if she sucks my thick cock. Turns out, she's not as prude as I thought she was. And when I catch her reading an erotic book, she shows me some of the filthy things she's been learning. A couple days later, I show my stepsister that I passed the big test with flying colors, and she rewards me with a cock ride that completely drains my balls.