The Lycaon Chronicles Book 1: Rivals In Alliance

"Mythology. You know, it's those stories about ancient heroes, powerful monsters, and selfish gods. What if all that wasn't just a story, what if it was real? What if those dangerous monsters walked among us? Lived with us? Acted like us?
Oh what am I saying, they are real, and I'm one of them."
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Castiel Lycaon, a hopelessly romantic, aspiring writer and the leader of the German Grecian gang, the Royal Bloods. At first glance he's normal, or as normal as you can get being in charge of a gang. But in reality there's something, mythical about him, about the whole gang.
The whole gang thing is a front, in reality the Royal Bloods are a pack, a mixed pack to be exact, primarily made up of elegant Lycanthropes and the guardians of the Underworld themselves, Hellhounds, and not just any Hellhounds, the regal Royal Tiger-striped Hellhounds.
They're not the only ones though, myths are everywhere, hiding right under the mortals noses.

Carol Deimos. At first glance you would think of her as normal too. She drinks, flirts, has sex, the typical mortal stuff at her age. But like our handsome Hellhound, she has something mythical about her too. Leader of the Snow Birds, a Grecian Italian gang, this classic lady of the century is a Gryphon, a Snow Gryphon to be exact.

He hates her, she's intrigued by him.
Normally a Gryphon and a Hellhound would have absolutely nothing to do with each other, but when ancient enemies come back with a thirst for their blood, they're forced into an alliance.