Last night talking with my stepsister while watching a show about sex she told me that she never masturbates. I didn’t believe her, but she swore that she has never ever masturbated herself in her entire life. I was so curious about it that the next day I decided to sneak into the bathroom while she was showering just to prove if she was telling me the truth or lying. She was naked and looked so fucking sexy soaping up her wet body and her juicy bubble shaped ass, her soaped up hands digging into the crack of her ass and between her legs. By the way she was rubbing and massaging her lathered up snatch there was no doubt that she was masturbating but that was the least of my problems because my sister had just realized that I was spying on her in the shower! She was mad at me for spying on her, but at the same time, she knew that she was busted, so she decided to drop the shy girl act and show me that indeed, not only does she masturbates just like everyone else, she loves to do it and it gets her turn on to have her very own stepbrother watching her rub one off, fucking hot! As she shamelessly rubbed and fingered her dripping wet cunt I reached out and fondled her perky ass cheeks. I rubbed her wet slit and I could tell how much she liked getting a helping hand from me. My naked step sister looked at me, gave me this devilish little smile, and got out of the shower, right herself up and followed me to the living room. She got down on her hands and knees and I rammed my hard cock deep inside her dripping with pussy from behind, fucking her doggie style. I couldn’t believe this was happening! Her juicy bubble shaped ass looked fantastic and every time I stopped fucking her she would push it back against my cock, urging me to keep banging her and to turn her into my little fuck slut. She pushed me back away from her and climbed up over me lowering herself onto my lap my cock slid slowly inside her slippery slit. She began riding my cock in reverse cowgirl style with her sexy ass bouncing in front of my face. I placed my hands on her buttocks and started pounding her as fast as I could. My slutty step sister yelled she was about to cum and started riding me faster. I fucked her sideways from behind and doggie style before blowing my load all over her naked body!