At that moment I felt the orgasm begin to take me. My thighs were trembling around my brother and my hips were driving against his as hard as they could. I was right on the edge and could tell Mark was as well. At the last second as hard as I could I pushed my heels into his sides and turned my ankles twisting the heels into his sides.

Mark let out the loudest cry I had ever heard come out of him, and with one final thrust his cock twitched inside of me filling me with squirt after squirt of his hot cum. At the first squirt of cum...