The giant snake in the cage perks up as soon as the door closes and looks at Terry like a cat after a tasty mouse. A door on the far side of the cage opens and Terry rushes for it.
She is much too slow. The snake strikes before she gets halfway, engulfing her head in one bite. It then throws a couple of coils around her to hold her and starts to dine, not bothering to squeeze her first.
Terry struggles, but does not even slow the snake as shoulders, breasts, waist, hips, legs, and finally toes make their steady progress into its mouth. In less than a minute, all that is left of Terry is a set of bulges in the snake that head down the snake towards its stomach.

Lizzy passes you a note "It can down several students at a time, so don't talk in class or cause any disruption, or..."

You nod your head and listen to the lecture.

It's very dull stuff. Amounts to a moral lecture about how vores should not eat humans, an opinion not shared by any vore present, including the professor who mindlessly reads the lecture without paying the least attention to what she is saying. The only reason to be here is this is a required course, and required by the humans who pay most of the bills to finance this place. So since they want it, you have to suffer it, no matter how worthless the course is.

Everyone else seems to share your opinion, but most seem resigned to sitting there for an hour. Some fall asleep. One is unlucky enough to start snoring, which quickly earns a trip to
Detention. He tries to just stand still once in the cage, which means he lasts a couple of minutes longer than the girl did, but either he moved a bit or the snake smelled him and it eventually strikes and he is quickly a meal.

The rest of the class is just as bored as you are. You are just looking for something to look at besides the clock that seems to have stopped, when you notice the agitated girl a seat or 2 away.

Looking closer, you realize the lad sitting between you has slipped to the floor and is devouring her feet. She faces a bad situation. Yelling or fighting to save herself will just earn her a chance to be snake food. But she is not going to be able to stop him from eating her otherwise. Some other students have noted her distress and are watching with amusement.