Belphegor notes

One of the posters over on the Ars board is doing some great stuff with Baal-peor’s mystery cult initiations. Check them out.

A few suggested additions for your saga:

In later demonology Belphegor is the demons of inventiveness, so he’s the one who knows where all of the Original Research is lost.
He may also be the one who causes it to be lost, by attacking people verging on breakthrough.
He’s the Infernal Ambassador to France, so he’s in favour of France being larger.  This is quite important for the French invasion of England early in the reign of the current king. He’s a possible replacement for Argenta, the demonic patroness of the French pirates in Antagonists.
He’s terrified of women, as noted in a folktale recorded by Machiavelli. See this Librivox page for audio and ebook versions of the story, where he’s called Belphagor.