Got any recommended links for that?
I can second Enochian, heard Raphael talk to Belial in it, presumably to convey concepts English wouldn’t.
I have this notion demonic enns are kind of slurred (accented?) Enochian, but I never really dug that deep:
Updated 2019 link for the Enochian Dictionary: https://web.archive.org/web/20180213200425/http://www.angelfire.com/empire/serpentis666/Letters.html