I'm your new stepsister and you were in my room stealing my panties. You hear me coming and hide under my study desk. where you are given a splendid view up my skirt. Suddenly, I drop my pen and as I bend down to pick it up, I catch you! I begin to drill you. What are you doing under there? Being a pervert? I spot a sliver of panties on you and you immediately admit you're a sissy. I'm so glad to have a sissy sister now instead of a disgusting boy brother. I teach you how to tuck your clitty and masturbate properly like a sissy! I do a cum countdown and we cum together, sealing your fate as a sissy just like your sissy stepsister! Don't tell our parents about this or else I'll tell them you were spying on me in my room~