I was somewhat concerned that it might be more of a zero-sum process, but was mostly sure that there had to be surplus value created in the act of mak...ng love. However, the law of diminishing returns was a real bitch. We were providing one another with less and less with each orgasm. No one wanted to be the first to say it, but I think we all knew what it meant. We were basically getting bored with each other. Our kind wasn't meant to stray far from home, it seemed, but all the same, we were. The heavy weight of the dog caused her to quiver with excitement because she could easily imagine what she must had looked like to the onlookers with her official Girl Scout panties down around her ankles and her absolutely naked stark white ass cheeks trembling in fear of the huge doggie dong behind her.It was the first time she had ever even though of the possibility that a dog could mate with a human female and she never had thought that she would be in the position of being spread open for. Dawn and Rose were in their 50’s trim well dressed and well groomed and drop dead sexy. They were in town on a vacation invited guests by some corporate hot shot that had come and gone not long after they arrived. We had caught each others eyes and being the bold brash gentleman I approached and introduced myself. Rounds of drinks later here we were lustfully staring at each other ready to pounce. They requested that I join them in an hour and gave me the room number where we were to meet. . I was too late his cock had slammed into me. Mike no!! I screamed. His hips were moving back and forth with force. My thin frame moving up and down under him. He freed my hands from his grasp. Immediately they went to his chest. I arched up off the bed. I never felt someone that powerful inside me. It felt so right but hurt at the same time. My legs wrapped around his waist. That is it darling take me inside you. he said. His hips moved faster and more power. He was not showing any mercy to me..