"So now what?", you ask. "I mean, how's this going to work going forward?"
"You mean what I'm going to do with you?"
"Yeah, something like that."
"Well, I have one idea."
"What?"
"Just stand back and don't talk."
With that, she strips herself naked. Even though you've changed genders, you still can't help but let all sorts of perverted thoughts flow through your head.
And then she notices.
"Careful, or you'll get your panties wet."
That's enough to get you to stop. Your girlfriend then turns to the machine and makes some adjustments. Then, she selects something and begins the process to change her physical form.
At first, nothing happens. Then you notice something. She's getting taller. It's happening slowly, but she's going from around her original five feet to six. And then her skin starts to tan, until it's the same color as yours. You can see her skin start to stretch and wrinkle, her ass fatten out more, and the nipples on her breasts turn dark and expand until they're as big as flattened half-dollars. Her hair gets darker and longer. But it's her face that undergoes the most striking change. Her face now looks just like yours, with the same narrow eyes, shaped eyebrows, and smooth jawline.
When it's all done, she walks over and pulls you close. You find your face squished between her boobs, unable to open your mouth. And apparently, that's just what she wants.
"Now listen here. From now on, I am your mother and you are my daughter. Your father left us a long time ago when you were an infant, and I don't know where he is. I work as a paralegal in a local law office that handles divorces, so I don't always have time to spend on you. You have your own friends, and do your own things. Understand?"
You make no attempt to respond. In your mind, you think "Wait, what? I didn't agree to any of this!"
But she senses your opposition. And she has a response.
"If you don't agree, then here's what will happen. I will use this machine to turn you into an embryo, and have you implanted in my womb. I will then be forced to birth you naturally, nurse you with my breast milk, and raise you as a baby, then as a little girl, then as a teenager, until you're old enough to get married and get the hell out of my house. You will forget every memory you ever had as a boy and for all intents and purposes, you will be my biological child. Now do you understand your position?"
You manage to wrench your head free long enough to signal your approval.
"Good girl. Now, let's get you ready for school."