My Girlfriend's Sister

"Oh, fuck," I groaned, as Katherine also moaned.

Katherine felt a little tighter than Emma, and the natural pressure of her pussy squeezing my dick felt glorious. I pulled all the way out and slowly pushed all the way in. Again, we both groaned. I continued this slow process over and over as pressure built up in my body. I was actually fighting myself to control the pace to make this last as long as possible. After having gone down on both women, I was pretty fired up, and I could easily blow my load quickly. But I fought the urge.

I leaned forward and reached both hands under Katherine to cup both of her breasts. God, I loved this position. I caressed her breasts as I took short strokes in and out. The shorter strokes helped me hold off my orgasm and allowed me to spend some time squeezing her nipples. I knew that Katherine loved nipple-play, and I didn't want to disappoint her.

I continued the short strokes for a few minutes, but the head of my dick was begging for more. After the extended nipple-play, Katherine seemed ready for more, too. I released her breasts and straightened up. I put both hands on her hips and started long strokes, pulling her into me hard with each deep penetration. As the pace built up, the sound of my body slapping her ass got louder, as did Katherine's grunting with each stroke. My entire body was tingling with incredible excitement as the smell of sex filled the room.

I knew I was getting close, but I wanted to make sure Katherine came first. I was just about to reach forward to be able to rub her clit when she suddenly cried out, and I felt her pussy squeeze my dick hard. I couldn't take any more, and I felt a giant release of cum shoot out my dick. The electricity that shot through my body with each pulse of my dick was incredible. Katherine continued squeezing my dick as her orgasm continued, and each contraction squeezed more cum out of me until I was totally drained.

I fell onto Katherine's back, trying not to crush her. She pushed her knees back, and we both fell down to the bed. My dick slipped out of her, and I rolled to her side.

I suddenly remembered Emma was in the room. I looked over at the chair, and her legs were spread wide and her eyes were closed. It was obvious she stroked herself to another orgasm as she watched us. Jesus, what a day!

Katherine turned toward me, with her back to Emma, and she smiled.

"Wow, that was nice," she said very quietly.

"Yeah, for me, too."

It was a little awkward to be laying naked next to one woman while my girlfriend was a few feet away. But then again, EVERYTHING about this evening was awkward.

After a few minutes, Emma said, "Shit, that was something!"

Katherine and I both laughed and agreed.

"I loved watching you guys do that," Emma said, "but let's get something straight. You two cannot fuck again..."

I was about to sadly acknowledge that with an 'I know', but before I could get it out, Emma continued, "unless I'm with you! We're here for another few days. Can we come back again, Katy?"

"ABSOLUTELY!" Katherine said while laughing.

And we did.