You hear a noise coming from Step-Daddy's room, the door is open slightly so you go and look. All of a sudden, your Step-Sister is thrown against the wall, being fucked hard, someone pounding her, making her moan. You get hard watching, her tits bouncing, she's so hot when she's being fucked from behind. And then you hear her moan 'Step-Daddy' and you're shocked. You film her, planning to confront her later, and to watch and jerk over.
When you finally get a chance to speak Step-Sister when you're both home alone, she begs you not to tell anyone, and persuades you with her balloon tits and tight pussy. Your cock is better than she thought, bigger than what she expected. You fuck raw, Step-Daddy always used a condom, but not you. You own her pussy now. You'll breed her, claiming her. You'll fuck her pussy whenever you want, because you're so much better than Step-Daddy.