Caught balls deep in Jennifer's ass when her Grandmother walks in!

I was only following orders, sort of. Jennifer did order me to fuck her and I did. She was trying to get me to cum and it didn't work the way she wanted it to. It started with her making me tell her details of my masturbation habits. She made me admit that I had problems with premature ejaculation when I was younger. She laughed and teased me for being a two-pump chump. Then she wanted me to admit how hot I thought she was. Then I think she thought that I would cum right away if I put my dick in a girl as hot as she is, so she ordered me to fuck her. While I would rather jack off than have sex, she did give me a direct order, and she is one of the hotest girls I've ever met, so...
After fucking the living shit out of her pussy, she commented on my not cumming and I told her that fucking her in the ass might make me cum faster. She didn't like the idea at first but it wasn't too long till she was willing to give it a try. First I told her I wanted her to ask me to fuck her in the ass, then I made her beg me to stick my dick in her asshole. I couldn't say no as she pleaded and begged me to "Fuck her virgin ass". I slowly started sliding my cock in her ass, going deeper every pump until finally I was balls deep in her ass. I started fucking her tight little ass and she was moaning for me to fuck her ass hard. She was pleading for me to fuck her ass harder and I went balls deep again and paused for a second. It was a shock to hear Mary, Jennifer's Grandmother loudly asking me what the fuck I was doing. I froze and didn't want to move, she told me to take my dick out of Jennifer and as I slowly pulled my dick out was when she realized I was fucking her in the ass.
Mary told me that she gave me to some of her friends that lived on a farm in Idaho and I would be leaving immediately and that I was going completely naked, of course. When her freinds arrived to pick up their new toy she asked them to punish me severely, which they seemed happy to agree to do.