You walk by your sisters friends door and see her changing. You peep on her until she is naked, but she catches you and drags you into the room. She is angry and says she is going to tell on you, but she sees how hard you are and she gets a better idea. You are to take your pants off and sit on the bed and edge until she tells you to cum. She teases you with her tits, spreading her ass, grinding her body on you, twerking and other sexual ways to drive you mad until you cant take it anymore. you tell her you cant hold it in any longer and she tells you you have to hold it in until she tells you to as she puts a hand on your cock you cum a ton all over her. She says unless you clean it off of her then she is going to tell. You do your best to clean up all the cum, but are left not knowing if she will actually tell or not.