Blood of the Sands by S.C. Grayson

Keera is used to protecting herself from the dangers of the Ballan desert. Guarding her heart may be the most difficult challenge of all.

Keera is an exile struggling to survive, forced to rob passing travelers or face starvation. When she steals from the wrong man—a vicious masked warrior named the Viper—his hand around her throat awakens an ancient magic within her, and she uses it to escape his clutches. Now, Keera must master her power to protect the city of Kelvadan—the only place an exile like her can find a home—from the Viper and his growing army.
The Viper serves the magic of the desert, but the sins of the past threaten to destroy it. To protect his home, he will do everything it takes, even marching on the great city of Kelvadan. However, the real key to healing the desert’s magic might lie in the infuriating but intriguing exile who slipped through his fingers and now fights for his sworn enemies.

Keera and the Viper are on opposite sides of a war to save the Ballan desert, but the strange bond they share could be the key to saving their home—or destroying their world as they know it.