Burn the Sky — Jaye McKenna

"What begins as a simple teaching assignment becomes both an affair of the heart and a life-or-death struggle. Cold-hearted Wytch Master Ilya must teach headstrong Prince Garrik how to control his dangerous Wytch power--or put him down, for the safety of all."
Prince Garrik is the Heir Presumptive of Altan, next in line to be crowned Wytch King. There's only one problem: in order for Garrik to be crowned, he must possess Wytch power of his own, and thus far, whatever power Garrik might possess has shown no sign of awakening. As things stand, it is Garrik's younger brother, Jaire - a dreamer completely unsuited to wear the crown - who will take the throne after their father.
Concerned about the future of his kingdom, the Wytch King demands that Garrik's power be forcibly awakened. Hoping to protect his brother from the burden of rule, Garrik allows the attempt - with disastrous results. Now, Garrik must learn to control the fiery dragon that rages within him before he destroys everything he loves.
Wytch Master Ilya has been alone for years. Learning to control the icy beast slumbering within him has already cost him his family and his lover, and Ilya will never open himself up to that kind of pain again. Summoned to Altan to avert disaster if he can, Ilya has no intention of allowing anyone to thaw the ice in his heart. When he meets Prince Garrik, sparks fly, and Ilya finds himself fighting feelings he thought he'd buried, long ago.
Can Garrik's fire melt Ilya's icy heart? Or will Ilya be forced to use his ice to quench the flames that burn within Garrik once and for all?