Eternal

Kai and Jericho. Two exiles from the Eternal Empire. Their paths cross in a nondescript Borderland moonbase, far from Imperial civilization. On the surface, it's an ideal situation. Kai needs a bodyguard, Jericho has all the necessary skills and then some, and they get along well in their initial meeting.
But then reality intrudes. Because Kai is a hunted man, pursued throughout the Borderlands by mercenaries and assassins. And Jericho is held captive and docile by a vicious restraining collar, sold into slavery years ago by his own father and exiled for a crime committed against a free man. So it's a cash transaction, not friendship, that brings the two young men together.
A close relationship springs up almost instantly between them, deepened and cemented by the adventures they share. Bounty hunters, pirates, and renegades keep the two exiles stepping lively about the Borderlands. The slave collar makes certain neither man does anything about the growing attraction between them.
Then Kai's mysterious past catches up to him in a way he just can't ignore. Because the Imperial Legions are out in force, hell-bent on catching the elusive exile for reasons of their own. And then he makes a decision which might just destroy everything.
Welcome to a world in which the Rome never fell. Instead, it conquered its home planet and grew into the interstellar Eternal Empire, a vast civilization powered by magic and slavery, where life can be mighty good for some citizens. Meet dragons, demons, and necromancers. See the repercussions of Kai and Jericho's actions. And above all, hold on, because it's going to be a wild ride.