My son 19M invited some friends over. I had just gotten home from being out with some friends earlier in the day and thought they all had gone somewhere together. I walk into my room and get undressed as I'm getting changed I hear from behind me "OMG wow" and I turn around and see my son's best friend naked. I look down and see his penis start getting erect and look back up at his face. He walks over to me and kisses me, I tell him that he needs to close his eyes and he does so as I make him sit down on the bed. I tell him he isn't allowed to open his eyes and he gives me a nod. I lick his balls and watch him smile, I gently stroke him for a bit and then stop. I hop onto the bed behind him putting my ass up in the air and face down and tell him that he can turn around. He turns around and without wasting a second I feel him enter me. He cums inside me after about 2 minutes as he was thrusting so hard and quickly into me. We both get dressed and agree that this can't be talked about again.