The Goblin Emperor by Katherine Addison.
What if the emperor was a decent guy?
Poor Maia is the 4th son of the elvish emperor, consigned to a remote manor with his abusive uncle for the crime of being born to a wife the emperor didn't like very much. Or at least he was, until the airship his father and three brothers were on exploded, making him the new emperor.
Growing up with no one to talk to other than a drunken uncle who beats you for fun is perhaps not the most standard training for emperorhood, but...