Balls deep in my sister's tight twat

So my Step-Sister, Riley Jean, is a total hotty. Ever since my old man married her mom I’ve kind of had a thing for her. Especially since she got back from College this summer. I can’t stop thinking about her and I probably jack off to the thought of her at least two times a day. I know it’s sick, but I can’t help myself. The other day she came home from the gym and she looked so freaking sexy. I decided to spy on her a little bit when she said she was going to take a shower. Once she got naked she began to stare into the mirror and touch herself. I got so turned on that I pulled out my cock and started stroking it right there. Unfortunately, she busted me dick in hand. I was so embarrassed until she told me it was okay and that she secretly had a crush on me as well. Well one thing led to another and soon I was balls deep in my Step-sister’s tight, hairy, twat.