Clark, C. L. (Cherae L.). Magic of the lost #3

"Luca is the new queen of Balladaire. Her empire is already splintering in her hands. Her uncle wasn't the only traitor in the court, and the Withering plague will decimate her people if she can't unearth Balladaire's magic. The only person who can help her wants the only thing Luca won't give-the end of the monarchy. Touraine is Luca's general. She has everything she ever wanted. While Luca looks within Balladaire's borders, Touraine looks outward-the alliance with Qazal is brittle and Balladaire's neighbors are ready to pounce on its new weakness. When the army comes, led by none other than Touraine's old lover, Touraine must face the truth about herself-and the empire she once called home. A storm is coming. Touraine and Luca will stand against it together, or it will tear them apart once and for all"--