Mending friendships, relationships with friends and foes, past/present/future, the creation of the world, bestowing titles
Basically a horse, though he can turn into a man if that’s easier to deal with.
Besides giving “dignities and prelacies” (civic and church titles and appointments), he’s a font of esoteric knowledge about the divine and the creation of the world.
Orobas is about as nice a demon as you can find. Apparently. Not only is he generally friendly and honest (and can keep other people honest), he goes out of his way to protect his pet magician from other demons and their temptations.
However, Wikipedia suggests a dark side to this otherwise nice horse. In fairness this isn’t a well-cited entry and has a rather Christian feel to it, but 1) this is a resource for writers and creators, and 2) it kind of has a ring of truth: Long term, Orobas will steer his magicians into an unchallenging life, tempting them toward sloth and away from developing into their full potential.