SOLVED. High fantasy novel involving a kidnapped(?) man, being rescued by his partner, and his half-demon son. [s]

[Jackson]

For whatever reason this novel I read as a child has been occupying my thoughts, and I have now compulsively devoted my entire evening to trying to find it, to no avail. I cannot remember the title, nor the author... But I do remember a scene from the novel. A man who has gone missing, and his wife/partner has gone searching for him, as well as his half-demon son. His half-demon son has two familiars, twins, that I think he found at the bottom of the ocean, or something as such. Someone has visions of the man, naked and bound in chains, at the foot of a live volcano, dancing (surrounded by, and this detail I am not as sure about, 100s of others) and though he hasn't been gone long it looks as is he has been gone for a while: his skin is deeply tanned, and his dark hair, on both his head and body, has been bleached by the sun.
I've tried any number of keyword searches in the hopes of finding something, but alas no. Any help would be greatly appreciated!

[Jackson]

The Gods Awake - Allan Cole

[Kate]

For the link: The Gods Awaken