Moving from Threesomes to Swinging

After a couple minutes in this position I looked down at Anna, planted a deep kiss on those luscious lips, and whispered "Bend over. I want to fuck you from behind." Anna quickly scrambled to her hands and knees as I moved behind her, burying my cock in one solid thrust. By that point Jake was flat on his back, and I had the perfect view of Rachel's bouncing tits as she rode him with a passion. As I continued fucking Anna she leaned forward to Jake.

"Do you like her pussy baby?" she asked her boyfriend.

"Mmm fuck yes. I love it." he responded as Rachel kept up her grinding.

"Oh Jakey," she continued. "Jakey he's so deep inside me. It feels so fucking good baby." I could hear their conversation, and the erotic nature of it, combined with her pussy wrapped around my cock and the view of Rachel's stunning body nearing another orgasm right in front of me, brought me close to the edge. I decided then that I needed to make Anna cum one final time, so I grabbed her hips and started slamming my cock into her harder than I had the entire night.

"OHH FUCK!" she screamed as I pounded her.

"Mmm yes baby!" Rachel moaned on top of Jake's cock. She braced her hands on his chest and began bouncing her entire ass up and down his dick, apparently determining to cum at the same time as Anna. I could see Jake struggling to hold back his own orgasm and I knew I wasn't far behind; I made sure to give Anna a couple more full and deep thrusts which finally pushed her over the edge. She didn't make a sound as her entire body clenched around my cock, and it was all I could do not to explode in her right then. Somehow I managed to hold on though; I pulled myself out of her soaked pussy and started stroking. I watched as Jake did the same thing, now kneeling on the bed above Rachel who was kneeling on the floor. He was working his cock the same as me, and a moment later we both moaned together; Jake shot his cum across Rachel's chest and neck, and my load landed all over Anna's ass. I collapsed to the side, completely out of breath and beyond satisfied. Anna was laying flat on her stomach, eyes closed and a large smile on her face.

"So..." she said after a minute. "What are you two doing tomorrow night?" Anna said at last. "Are you two free tomorrow night?"