Duel of Fire by Jordan Rivet

Dara Ruminor is a competitive duelist about to take the kingdom of Vertigon by storm. In a world where swords are used for sport and athletes live like kings as long as the crowds love them, all she needs is a wealthy patron to help her achieve dueling glory.

Instead, she gets Prince Siv, the heir to the throne.

She’s supposed to train with him, but it isn’t as easy as it seems. Handsome, charming, and utterly infuriating, he refuses to take the sport—or her—seriously.

But Prince Siv might not be learning the sword just for fun. As threats emerge from the shadows, with the careless prince as their target, Dara will have to raise her sword to protect him—but even her skill might not be enough to keep them both alive.