Silk & Sand by Katherine Diane

The only thing worse than trekking across a dangerous desert on a nearly impossible mission? When your guide is intolerable—and irresistible.

Seth spends his days hunting down mystical artifacts. As a Curator for the Arcanum College, that’s his job. But when an arcanist murders a fellow scholar, Seth finds himself assigned instead to a dusty, thirsty, frustrating manhunt. But why him? Because, he’s been told by his superiors, he’s the only Curator sufficiently tenacious and brutal for the job. (Seth resents that.)
When the murderer vanishes at the edge of a deadly desert, Seth finds himself in need of a guide. Unfortunately, the “only one crazy enough” for the job is Raider—a man with an easy grin who is clearly a thief, liar, and rogue. (He also has illegal quicksilver in his veins, and that arcane enhancement positively screams “I’ve done bad things.”) The only thing worse than having to rely on such a reprobate? Finding him irresistibly attractive.
Raider might think the manhunt a foolish endeavor, but he’s delighted by the prospect of breaking past the barriers of the gorgeous, rigidly self-controlled Curator. That kind of intensity needs the right outlet (and Raider has such ideas). But Raider just might be asking for more trouble than he realizes—because he has barriers of his own, and some very dark secrets lurking behind them.

But that’s not the only trouble looming. Because if Seth and Raider can survive their desert journey? Seth’s manhunt will lead them into even greater dangers and mysteries.