Your aunt, who is your mum's step-sister so looks exactly like your mum, is catching up with her favourite nephew and being pretty full on flirty... You're not sure what to make of it as she teases you about how much she looks like your step-mother, and makes you tell her that she's the sexier step-sister... She tells you about the trouble people have telling her and your mum apart sometimes, and confesses that once your step-dad actually flashed his cock at her for a second, thinking that she was his wife... This leads her to wondering aloud if you've inherited your step-dad's sizeable penis, and before you know it she's somehow got you to get it out and show it to her. Telling you that you need an experienced woman to guide you and teach you a few tricks, she takes it in her hand and begins stroking, disconcerting you by occasionally reminding you that she looks so much like her step-sister that it's almost like your mum is the one jacking your cock right now