I haven’t read through The Worm Ouroboros in 45 years. How Eddison likes to describe clothes, architectural details, banquet items, etc.! The gorgeousness and magnificence remind one that medieval fairies were human-sized or taller and lavishly clad. Indeed, Eddison’s Mercury might be Faërie. (The nomenclature of Imps, Pixies, Goblins, etc., however, is a bit of a shock for a first-time reader.)
I wonder when the idea became explicit that fairies are soulless. It might be implied in medieval imaginings, but I’m not sure that it was ever stated then. Eddison’s fairies seem soulless. The Witch-king decorates his castle with the skulls and bones of those whom he has killed in single combat, the palace is of black stone, his crown is a menacing crab fashioned of iron and jewels, etc., and Gorice XII is a necromancer; but one doesn’t have the sense of the Witches as people who are fallen. They are true to their nature, while, in a serious conception of good and evil, creatures have somehow become evil; this might be considered in terms of a corporate fall (In Adam’s fall we sinned all) or bad choices made by an individual that lead him deeper into corruption (Macbeth, originally a good soldier). Either way, the orthodox understanding is that even “the Evil One” is not true to his original nature, though now, when he lies and kills, he is true to the nature that he has become. Nothing like this is going on in The Worm Ouroboros. The people are true to what they are.
It’s an aristocratic world like that of romances and, for the most part, the sagas, all about honor (or treachery), strength, beauty -- being seen as excellent by those whose esteem matters. One could conceivably be shamed but one cannot be guilty.
Those would be some observations so far (into Chapter 8). When Brandoch Daha refers to God and the devil (p. 131), these are named merely to express his lordly warning to anyone who would try to get him out of bed before he chose to rise. Juss laughs and leaves him in peace.