Ask her what's going on

There's no doubt that she is in your complete control now. But how? Why? You certainly don't know. But she's the one who just sucked you off in her office. Maybe you can figure something out by asking her!

"Professor Porter," you begin, then chuckle. "I mean, Gillian. Be completely honest with me, now. Tell me why you're doing everything I tell you?"

"I...I don't know!" she confesses, still on her knees, a drop of your jism running down her chin. "There's this strange pressure in my head. I could resist it at first, but it got stronger and stronger every time you told me to do something and then suddenly, it just seemed inevitable. I don't understand it, but I know that I'll do anything, even >be< anything you say! I should be terrified, but all I feel is submissive."

Then in a very small voice she admits "I even kind of like it..."

You grin.

"Oh, that isn't true," you correct her. "You need to like it a lot! You should love it! You love being my **** girl! It completes you! It fulfills you! And it makes you oh so very horny!"

Your kneeling professor's eyes go blank again, and when light comes back into her eyes, she looks deliriously happy and devoted to you.

"Oh Master!" she cries. "Tell me more! What do you want me to do now?"