Each thrust resulted in a feeling of something pressuring my pussy lips to extend, something growing and becoming larger with thrusts. My mind cleare... just enough to recall animal anatomy and specifically that of dogs … the knot. The knot was forming and would be pressed into me, tying us together. I knew the physiology of dog mating. Even thinking about Bo doing me, absently in my mind, I had forgotten that aspect of canine mating. Being tied together.The knot was being pressed into me. It is just that there is not much space around us, and that I have to rest my hand somewhere. I initially wanted to indicate that she was authorized to get closer to me. No second thought.She stands still.My hand is still on her hip. I sense that she starts to relax.I never intended to stop focusing on the play but I start now to discern her silhouette, to smell her hair, to guess how she is dressed, or to watch the allure of her back. She has now most probably guessed that I don’t have. She was so worried that her romp in the pool with Steve and Frank would be discovered that she was paranoid and remorseful. Bill, her husband, didn't notice a thing, but Heather knew something was bothering her Mom.The next week at school, Steve and Frank, like most teenagers, boasted about the fine piece of ass they fucked after they left the party Friday night. They never said who it was openly, but the worldly Jake was able to privately worm the name of Mrs. Kelly Beal out of his best friend. She screamed, “Bitch! That was hot,” and laid down for a minute. Then she started at my dick again. This time she used her teeth as she went down inducing a pleasurable pain.I dug my face again in her pussy and started sucking her clit and slapping it with my tongue. Did that for a few minutes, and then I inserted two fingers from the top and . Sandy was moaning and sweating. I was eating her clit like there is no tomorrow and finger fucking her slowly.In between, I took my fingers and extended.