Black God's Kiss by C.L. Moore

A fierce young countess, proud and unyielding, pursues vengeance into a nightmare realm when dark sorcery and a malign cult threaten her homeland; she crosses a bleak, otherworldly landscape, confronts unnatural beings and a terrible god, and must rely on courage, cunning, and sheer will to survive. The tale blends sword-and-sorcery action with gothic atmosphere and a focus on personal honor, testing the heroine with supernatural horrors and the cost of defying forces beyond mortal ken.

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