The ruin of kings - Jenn Lyons

When destiny calls, there is no fighting back. Kihrin grew up in the slums of Quur, a thief and a minstrel’s son raised on tales of lon-lost princes and magnificent quests. When he is claimed against his will as the missing son of a treasonous prince, Kihrin finds himself at the mercy of his new family’s ruthless power plays and political ambitions. 

Practically a prisoner, Kihrin discovers that being a long-lost prince is nothing like what the storybooks have promised. The storybooks lied about a lot of other things, too: dragons, demons, gods, prophecies, true love, and how the hero always wins. Then again, maybe he isn’t the hero after all. For Kihrin is not destined to save the kingdom. He’s destined to destroy it.