Don't know title, not sure of genre

[hecatemahadevi]

I never actually read it. I saw the cover in a collection of sci-fi/fantasy book covers I know the local library used to have (they may or may not still have it; this was probably 20 years ago, and I know well-loved books get "retired"). What I remember is that the cover was dark, i.e. a night scene, and showed a pale-skinned woman with black hair and a flowing black dress, holding a large glass goblet of blood. I would assume it's something in either the high fantasy, or low/urban fantasy genres (vampires maybe? or just witches?) but I can't recall anything about the title, the cover's artist, or the author of the book it went to.