Carissa is summoning a demon.
So are fourteen other people; it's a standard class, for new fourth circle wizards. Mostly they've summoned devils but for the sake of thoroughness -- situations might come up where you'd prefer a demon, they're often cheaper to pay and they have different capabilities -- they're going through the other evil outsiders too. Not the neutral ones, and she's not sure why but obviously isn't stupid enough to ask and let on that she's not sure why.
Carissa has been at the top of her class since she was twelve years old, all the lashes on her back are visibly from before her pubescent growth spurt, and she feels very strongly about keeping it that way but it'd be stupid to rush to be the first to get her demon summoned, lest she make a mistake in the wording on the circle she is writing in powdered cold iron.
She is instead the second to get her demon summoned.