"I'm not sure," your girlfriend, Janet says. "I have an idea of what I might like to turn into though. I'll try it out and if you like it, we can both be the same thing."
Before you answer, Janet closes her eyes and kind of hums. Suddenly, her eyes pop open and she gasps. "Hey, I thought my clothes were supposed to disappear," she says as a grin spreads across her face.
Her jeans and shoes vanish. The small pink shirt that she's wearing starts slinking up her body. It twists itself around her neck and transforms into a collar. Out of nowhere, a small, silver, bone-shaped tag appears on it. Janet grabs it and reads what it says aloud. "Janet, Room 329. That's pretty cool. Well what do you think so far?"
You just watch, stunned. You sit down trying to hide the instant hard-on that you've gotten from the sight of your naked girlfriend. As you watch, you notice light blonde fur spreading across her shoulders. You also notice light pink bumps developing on her stomach.
"Mmmm, I'm really liking this," she says. "Evidently you are too." She comes over and kneels in front of you. Janet leans in towards your crotch. You start to feel a wetness in your crotch. Before you know it, your cock is out through your fly and in her mouth.
You moan trying to hold back from exploding. Her blowjobs have never been this good. Someplace in your mind you know that it is because of her transformation. You dimly notice that Janet has grown a long tail that is now wagging back and forth behind her. As she continues to suck, you feel like her tongue is traveling further and further down your cock.
She slowly slides her mouth off of you. "Wow, you smell so good," Janet says almost dreamily. She looks up at you and you are amazed at her face. Her eyes have turned a dark brown. Her nose has turned black and her face has started to push out into a muzzle. A light coat of blonde fur covers everything. She leans back in and gives your cock a quick lick. You are surprised that a dog's tongue has shot out of her mouth. It's roughness stimulates you even more.
Janet holds your cock in her hand. You can feel the roughness of the pads that have obviously formed on her hands. "You know this would be so much better if it was a doggy cock. Wouldn't you like to be a dog too? When we would finish transforming, you could take me just like a dog. I know how much you've wanted to take me like that." As she sex talks you, Janet continues to stroke your cock and lightly lick at its head. "Well, what do you say? You wanna give doggie her bone?"
You lean back and close your eyes. You erupt into her mouth. As you are erupting, you see a chocolate lab in your mind. It has a red collar with a gold dog tag. The red collar is the exact same color as your shirt. As you open your eyes, you look back down at your girlfriend. She smiles and you finally notice that your clothes have vanished. You are instantly hard again as you realize that you are changing.