I want to throw trivia out there, because after all, I am a trivia whore. Hello, NTN! Or Buzztime, or whatever the hell they are now.
Speaking of Hell: Here is the standing hierarchy of the Hells as of A Break In The Balance:
The Overlord
Azbaelus
Baal
Azmodeus
Astaroth
Belial (aka Pestilence)
Mephistopheles
Valfour (aka War)
Malefis (aka Sorrow, Fallen, Old One, Singer)
Much like Dante’s vision, the Hells are broken into 9 spheres. Unlike Dante’s vision, each one does not necessarily represent a single sin, but each is ruled by a Prince, and the clime of that sphere is subject to the Prince’s whim. The vast majority of demons are unranked and unnamed, implings being the most common. Named demons are far more powerful, and hold ranks among the courts of the Princes.
More to follow, perhaps on the individual Princes, although be warned: in one book or another, you will eventually meet them all.