Fuck her in the ass!

I continued to fuck her bent over the desk, my thumb plunging into her ass. She moaned, and her skin was covered in a glistening sheen of sweat. I was getting ready to shoot my load, but I didn't want to just pull out and spray on her ass. Since she liked my thumb in her ass so much, I thought I'd try giving her the real thing. I pulled out of her pussy and I removed my thumb from her ass. She gasped and panted, probably thinking I was done. Instead I positioned my dick in her asshole and pushed. She pulled away as she felt me push, but I grabbed her by the hips to hold her there, and I pushed again and felt her ass open up for my cock.

"Owww! I thought I told you to ask permission first! That hurt!" She said.

"You seemed to enjoy it,"

"Yeah but I was getting used to having your thumb in my ass, and then you went and shoved your big old dick inside my tiny butt. You can't expect that not to hurt."

"I'll go slow." I said, slowly pumping my cock in her ass. I kept just my head in, when she was getting uncomfortable I started to pull out.

"No! Don't pull it out! Just, let me get used to it. It will hurt more if you keep pulling it out and pushing it back in." I could hear her taking deep breaths. "Just stay still, and I'll back up on you. Once it's in all the way, you can start humping." Always do what the nurse says, I thought to myself.

She slowly backed up on my dick, taking it slowly into her ass, inch by inch. After a few minutes my balls were touching her pussy. She groaned a bit before finally saying "Ok, you can start pumping my ass now."

I slowly started fucking her. Each thrust elicited a moan of pleasure from Samantha. I slowly sped up my rhythm, and I could feel my orgasm building. She was bucking up on me and groaning. Finally she screamed "Oh god! I'm coming!" And that sent me over the edge. I grabbed her hips and slammed my cock all the way in. I felt my balls slap her clit as I shot a load in her ass. I pulled out, and left a little trail of jizz from her asshole running over her pussy.

Samantha quietly got dressed. She kissed me hard on the mouth.

"I have to head home and make sure the kids have done their homework. Next time just ask if you want a good fuck."

She was almost out the door before she turned to me and said with a grin:

"Oh, and delete the pictures."