Bonds of Brass by Emily Skrutskie

Ettian Nassun’s life was shattered when the merciless Umber Empire invaded. He’s spent seven years putting himself back together under its rule, joining an Umber military academy and becoming the best pilot in his class. Even better, he’s met Gal Veres–his exasperating and infuriatingly enticing roommate who’s made the Academy feel like a new home. But when dozens of classmates spring an assassination plot on Gal, a devastating secret comes to light: Gal is the heir to the Umber Empire. Ettian barely manages to save his best friend and flee the compromised … Read more.