Drinker of Souls — Jo Clayton

LIFE-CLAIMERS
She was Brann, the Drinker of Souls, from whom all but the very brave and the very foolish fled in fear. Bonded to twin demonic shape-shifters, she roved the land in search of rich life source to feed her demons' need.

But Brann too had a need that couldn't be denied, a quest to free her family from the evil king who'd enslaved them--a quest that would lead Brann and her unearthly allies into magical realms ruled by witches and werewolves, lawless lords and murderous villains, and the ever-present ghosts of the restless dead....