One Finger Challenge Turns Into Fuck

As I was passing by my hot stepsister Paulina's room the other day, I noticed her wearing sexy red lingerie and taking selfies. I thought that she was just trying to make a provocative selfie, but her tight young body was so appealing in that lingerie that I simply had to stay and watch her do it. To my utter surprise, she started slowly peeling off her clothes and admiring her naked body in the mirror. Her delicate stature, her round boobs, her completely shaved pussy, her belly-button piercing accentuating the flatness of her stomach how long have I wanted to see all of these things. And there she was, her steaming hot and naked body on the display, trying to do a One Finger Challenge. If you are unfamiliar with this challenge, it is basically chicks trying to cover their private parts (both the tits and the pussy) with just one finger while taking a selfie in front of a mirror. It is a really difficult thing to do, so I stood there watching my stepsis fail again and again. So, I decided to help her out. Sure, she was shocked to see me at first and tried to cover her nude body, but when she heard my proposal she accepted it immediately. But, as I was helping her out, the closeness of those out-in-the-open hooters and that bald beaver gave me a large boner that was totally visible in my pants. Sure enough, my lusty sis noticed it and, with a rather naughty look in her eyes, approached my crotch area and pulled out my rock-solid cock. Its big size surprised her, but she got turned on even more by it and immediately went on to suck it for a bit. She must have been very wet, because very soon after that she turned her back towards me, leaned down on the bed and let me penetrate her juicy snatch from behind. After I fucked her for a while in the doggystyle position, this foxy beauty made me lay down on the bed and started riding my throbbing member in the cowgirl position. Then, she turned her cute butt towards me yet again and went on to bounce on my shaft in that position as well. When I could not keep it in my balls anymore, I had stunning Paulina get down on her knees and suck me off before I ended up covering her pretty face with white sperm.