Shouldn't Of Happened

My 16 year old nephew is cheeky in a playful way. I join in just for fun at times. He came by once when he should of been in school. I was just in my bedroom and he was being very cheeky in a sexual way saying he would fuck me, but i might be disappointed. I got lost in the moment and said to him "im game if he was."

I let him see me take off my underwear and layed out on my bed. I've never seen anyone take their clothes and have their cock in me that fast before. For the short time he managed to last he kept saying "oh fuck, oh fuck." I happened to look at the mirror and knew it shouldn't have gotten that far. The moment i asked him to stop he started to cum grunting until he had nothing left.

There wasn't anything wrong with the sex, it's just that if anyone found out, it would destroy the family.