Tonight is a special night for my Stepson because it is "Prom Night" for him. I walked into his room that very moment right before he put on his tuxedo because I knew he would be sitting there in his underwear. "You must be so nervous since after fucking your prom date tonight you will no longer be a virgin, " I said to him. He tried telling me to stop talking to him about sex because it was very awkward to speak about it with me since I am his stepmom. I assured him that I was only there to help and to insure that he gave his prom date the fucking of her lifetime. I could see the bulge growing in his underwear. I told him that unless he wanted to cum the moment his girlfriend took her clothes off for him to stand up and let ME devirginize him. That's all it took, my stepson let mey suck his dick as I explained in detail to him that he should do with his dick once it was wet and full of his girlfriends saliva and that is to use that saliva as lubricant and to insert his dick in her. Like a good stepmom I spread my legs to give him a proper demonstration of what exactly he should I meant. His dick felt sooooo good stretching my pussy open, I always knew my stepson was endowed but never thought this endowed. I guided him to fuck my brains out until he was ready to explode his load of semen all over my ass. As I laid there with his load of cum on my ass cheek I said to him, "That was really good for your first time, your girlfriend is going to be really satisfied, BUT if YOU still aren't satisfied when you come home just knock on my door and I will let you fuck me again, have fun at prom.