I do not know either. It's not what you think of when you hear the word, Hell. But Lucifer is entering into his time of Sleep. Demons and Angels and the like maintain their long life spans by entering centuries long periods of Sleep. And it is apparently the ruler of Hell's turn. So they need a temporary leader. Each fact has a candidate, but they need someone to choose them.

For some stupid reason, it's me. Really when I have more important things.

[Like, much as he disapproved of such things, it seemed like Hell would have been much better of choosing the successor based on Prigmoture. Normally you risked putting a complete dud with no merit in charge, but Camio, Lucifer's actual biological son was hardly any sort of incompetent.]