This book is pre-order until book delivery arrives. 
 
Between Sky & Sea by Leena Kazak:
 
He was raised to destroy her kingdom. Now she's the only thing he refuses to conquer.
Prince Zevayr of Arbinj has built his name on fear and blood. As the Dark Commander, he is a weapon first and a man second-honed for war and hollowed out by loss. The battlefield has taken everything from him, including his closest friend, leaving behind something sharp and cold, more monster than man.
 
When he's ordered to escort his brother's betrothed back to Arbinj, he expects an inconvenience. He does not expect her.
 
He doesn't hesitate. He doesn't regret. And he certainly doesn't have room for love.
Mayah of Tundrayn is the crown princess of the kingdom that killed his friend-and everything he was raised to despise. Yet she's defiant where she should yield, soft where he is sharp. She was raised to see him as a monster, but she looks at him like she sees the man beneath the Dark Commander's cloak. As they travel across rebel-torn lands, Zevayr's icy barriers begin to melt, and he does the unthinkable-he loses his heart.
 
Back in Arbinj, where the glittering court is eager to see Mayah fall, Zevayr faces a new war-one that demands he choose between his duty ... and her. Because the harder he falls, the deeper the knife twists in his heart-and Zevayr learns the truth doesn't always set you free.
 
The question is not whether Zevayr will defy his kingdom-but how much of it is he willing to burn for her?
 
Author's Note: It is highly, highly recommended that readers first read BETWEEN TIDES & THUNDER in its entirety before reading BETWEEN SKY & SEA. The internet-breaking, heart-wrenching, soul-crushing experience will not be the same otherwise.