Lucifer's Castle — Tessa Tremaine

At the notorious brothel Lucifer's Castle, all the whores are Demon Kin, a humanoid race genetically engineered to possess horns, tails, and an insatiable sexual appetite. Demon Kin males Seth and Jude are lovers, best friends, and allies in a secret struggle against Demon Kin enslavement. They'll do anything to lead their people to freedom.

Rich, powerful Genevis Belleren is the perfect hostage for a couple of Demon Kin slaves bent on escaping their masters. She's also the most desirable woman Seth and Jude have ever met, and her lust for them is unbounded. But a permanent attachment to her is out of the question. She's a human, and she belongs in the human world.

Genevis finds herself falling in love with the charismatic men who kidnapped her. She'll do anything for them -- even oppose her uncle, one of the most powerful men in the galaxy, in order to join her lovers on a primitive desert world that has killed everyone who attempts to tame it. But will they ever love her in return?

Warning: this book contains graphic m/m, m/f, and m/f/m sex, as well as themes of dominance and submission, spanking, and a down-and-dirty orgy with aliens in the desert.

Book Four in Tales Of The Demon Kin; a story of the founding of the Demon Kin world, Belleren.