Darkness Returns by Alexandra Ivy

More powerful than ever, the Guardians of Eternity are facing their greatest challenge yet: a war within their ranks. Their future is in the hands of one rebel vampire, who must choose between loyalty and love . . .

Blessed with an even more compelling allure than most vampires, Chiron has made a fortune in the human world, creating an empire of resorts and casinos. Since the betrayal and imprisonment of his master, he has existed outside the order of the Guardians, trusting no one. But now, the new vampire king has given him a peace offering: a scroll that could free his master. Following the relic’s magic leads him to a demon hotel deep in the Everglades, a lush paradise owned by a mysterious and
mesmerizing woman . . .

As far as Lilah knows, she’s lived her entire life within the confines of her enchanted estate. Memories of her own past are elusive and cloaked in shadows. Even Chiron can’t figure out exactly what she is, and if her intoxicating beauty is his destiny or an illusion drawing him ever closer to his demise—or perhaps to an even more tormenting choice, between his master and his mate . . .