This is the demon Ayxgrouptaqpx, teaching Sowbristle University's Advanced Class in Subversion of the Astral Flume. She isn't supposed to be.

Ayxgrouptaqpx has just eaten Dr May Patella, who succumbed to complacency during a demonstration of the Flume. Ayxgrouptaqpx realized her own error within seconds. The demon is still held by the late doctor's summoning spell, and she is alone with the Students. They are third-year undergraduates, which is to say that they have survived vicious practical classes, digested texts of mind-scouring tedium, had their deepest desires laid bare and mocked during the infamous Sunday Tea Tutorials, had large parts of their souls stolen and sold for drink by the Master of The Deep, and have come back each semester for more. Their eyes, fixed on Ayxgrouptaqpx, have all the warmth and pity of the infinite Void, and she feels them waiting. She has no choice. The protective charms on the podium are fingernails on the blackboard of her aura, and the late Patella's notes are in execrable crabbed script. "The flum... flup... is composted of fragmunks... ments of unfirmed shoal... soul?..." Her hearts seem to collapse as she hears a front-row Student make theatrical snoring noises.