You feel a pain on your hip that reminds you of cattle being branded. That can't be precisely what is happening here, but it's a good bet that is what it amounts to. You have just become property of Charles.

"No mercy for you, you little twit. You digested my clone, and when your master gave you an extra chance to get out from under, you tried to eat him again. You are his property and he can do what he wants with you, whether that is sex, vore, or making you clean up that mess he calls a room."

Pulling out a vial, she commands "Drink this." You correctly conclude the stuff is not to do you any good, and resist, or at least try to. But tied down, about all you can do is keep your mouth closed, and when Charles gives your ass a pinch, you can't resist opening your mouth to object, only to have the potion shoved in. Considering your expectations, it doesn't taste bad, but...
"There. From now on, you will be able to vore only when your master wants you to." You had been starting to wonder if you couldn't escape by eating Charles tonight. Apparently they have thought of that too.

"Now Charles," you feel the secretary bending down and doing something with the chains around your feet. "Press here, and the chain expands so she can walk or spread as desired. Press here, and it contracts until her feet are forced together. Got that? Good. Now around to the front..."

The same procedure is followed with your hands. Being a clever lass, you keep track of the pressure points, but now the Secretary tells you to try them. To your surprise, you can't make them work. "These are Charles' chains. He can let you change them, but if he doesn't want to, you can't."
Another hope shot down almost before it is formed. "Now we loosen the chains enough to get your arms behind you ... right. And then tighten them so you are about holding onto your ass cheeks. And loosen the legs enough to let you walk ...
"Now collar and chain around neck ... OK, she is all your's. Take her away."

You try to resist, but Charles is bigger than you, and quite a bit stronger. It is not long before you realize you are going where he wants. So you salvage a tiny bit of dignity by walking.
Not that you can salvage much. There are a number of students in the hallways, and they seem to all recognize what has happened to you. Most seem to sneer at you for being so foolish. A few seem to pity you, which seems to hurt just as much.

But they really don't matter. What matters is ..."Charles.."
A jerk of the chain and "You call me Master now. Maybe if you are a good girl, I may let you use my name, someday."
A small matter under the circumstances, so ... "Master, what are you going to do with me?"

"Well..."