Return of the Vengeful Queen by C.J. Redwine

Charis Willowthorn is a queen without a throne. A Rakuuna invader holds Charis’s kingdom of Calera captive, leaving her desperate—and ruthlessly committed to vengeance. But with her allies reluctant to intervene and her enemies hunting her across the open sea, Charis is left with only one choice: forge a temporary alliance with Tal Penbyrn, the boy who betrayed her—and, at all costs, keep him out of her heart.

Tal is imprisoned, both by the Rakuuna and the weight of his guilt. Though he once betrayed his love, he knows that he can help turn the tide in Charis’s favor, if only he can regain her trust. But the Rakuuna have an ally of their own—one who knows Charis’s every move and will stop at nothing to see her destroyed.

With threats closing in and every allegiance in doubt, Charis must be stronger, faster, and more vicious than her enemies to reclaim her kingdom—and her future.