My stepson was looking in my panty drawer when I walked into my room, DEFINITELY not what I expected to see! Obviously I was upset at first but I started to get flattered and to be honest I just got horny. It was his BIRTHDAY so I got an instant idea of a gift for him. I was wearing a tank top and some tight yoga pants and asked him to sit on my bed and I seductively removed my clothing. He was in shock but was definitely not trying to stop me. I began to put on different pairs of panties to show off my amazing ass to him. I tried on different types of panties and as I was trying them on he grabbed my ass. I looked back at him and said, "look, but don't touch." but he still got a good squeeze. After I was done teasing him I completely removed my panties and showed him my bare ass, I mean I put my ass right up to his face and spread it so that he can see my pretty little asshole. I asked if he wanted to lick my asshole. Of course he did, he buried his face in my ass, I couldn't help but notice he had quite the erection. However, it is his special day so therefore I must do something about it, right? I removed his pants and took his dick in my mouth for a few moments until he was nice and hard. I got on all fours so that he could spread my ass and fuck me. When I turned around I caught him trying to put on a condom and that just wasn't going to work. I made him remove it and made it clear that tonight for his birthday he gets my pussy bare. He fucked me from behind for a bit so that he can see my ass bouncing against him and up against his balls, then I told him that I want to see his face as he fucked me. I got on my back and spread my legs and he ramed my pussy nice and hard. When he was close to cuming he asked me where I wanted his cum? "Cum inside of me," I said. He is taken back for a bit then asked if I was on birth control. I let him know that I wasn't but that I was serious about having him fill up my pussy with his cum, "it's my birthday present for you." It didn't take much convincing and he ejaculated deep inside of me. I wonder how he will react next time his friends tease him about having a hot stepmom since it seems to always happen.