Exploited My Stepsister to keep Her Secret Safe! StepBrother Takes advantage of Stepsister Ends Up Fucking Her Hard!

I got of work a bit earlier than usual, and I found My little stepsister masturbating while talking on the phone with her boyfriend! this is unacceptable and our parents would have punished her very hard for that! I couldn't leave that opportunity go away... I had to exploit her to keep it a secret! I had to fuck her! i wanted it so much since she moved to our house!