Don't Tell Stepdad

Your step-sister confesses to you that she's damaged your dad's car with the heel of her shoe as she's sat on the floor in her little skirt taking them off. But now she's worried you're going to tell him, but you won't if she does you a cheeky favor... if Aston lets you perv up her skirt and lets you wank your cock over her pussy, you won't tell her stepdad!