Accidental slip-up

Jon paused. He wanted to become Karyn's pussy, but savored the moment before he would change for a month. Suddenly, Jon's German Shepherd Sadie burst into his room. "Sadie!" Yelled Jon, surprised. Suddenly Jon was filled with dread. He had just said: "I wish to be the pussy of-" pause "Sadie!" The world tilted around Jon, and he blacked out.
When he came to, he realized he was facing the carpet and could only feel his face. "Damn!" Thought Jon. He was stuck as his dog's pussy! His mouth hung open ever so slightly, and it was pointed vertically. Try as he might, though, Jon could not close his mouth. Suddenly his view shifted and Jon saw both the bottom of Sadie's tail and her hind legs. His view shook slightly with every step Sadie took. He hear Sadie whine, and it sounded louder than normal.
"Wanna go out, girl?" Jon's sister Zoe said. Jon mentally cringed and tried to cry out, but could neither move nor speak. He heard the sound of a door open, then saw as Sadie entered the back yard, Jon suddenly felt a pressure in the back of his "throat." It rose until he saw Sadie lift her hind leg, shifting Jon's view sideways. "Urk," thought Jon as piss began spewing from his open mouth. It seemed to go on for ages until it slowed to a dribble, then stopped. Sadie trotted over to the back door and scratched until Zoe opened it. Sadie immediately went to the living room, sat down, and began licking her pussy, Jon's face and mouth. Jon was partially grateful as it took most of the piss taste away.
"Getting yourself ready, huh, girl?" Chirped Zoe. "Yes, Mr. Johannsen's dog will be quite the lucky bastard. I can't wait for puppies!"
"Oh shit," thought Jon as Sadie stopped licking. She was about to mate!