once we got to the dog park I decided to throw a little frisbee with my mom. I tossed it and she went out, caught it in her mouth, and brought it back to me. "Good boy!" I said. I started to pet her and she rolled onto her back. Seeing this I started to scratch her stomache until she got up. she walked over to a tree and lifted her leg. My mom then let out a stream from her canine penis. Mo mother was marking her territory! Once she was done with this she proceeded to trot over towards one of the female dogs with her tail held proudly upward. When she reached the female she sniffed at it's butt for a second. The female took this as a sign, and seeing she was in heat, lifted her tail to present her pussy to my mom. My mom's penis quickly grew out of it's sheath as she became aroused. She then mounted the female and started to pump her new organ in and out of the bitch. Seeing this totally freaked me out. "I wish my mother would go back to normal" I said in a desperate attempt to get the images that were going on before me out of my head. All of a sudden my mom (the male dog) started to change. The fur on her body started to recede into her body. Her breasts became larger as her penis began to shrink. Her face became human as her tail dissapeard. She was totally human again. She was still, however, humping the dog. It was a funny sight. A grown naked woman humping a female dog in the middle of a park. she screamed as she tried to cover up her newly re-formed breasts and vagina. The female dog had enjoyed the fucking and I guess before I had turned my mom back to normal, she had already came inside the female dog...Mom was going to be a dad!!!