The Girl King / Mimi Yu.

Enhanced descriptions from Syndetics:

"An absolutely fantastic tale of legends, magic and destiny." --Kendare Blake, #1 New York Times bestselling author of the Three Dark Crowns series

Two sisters become unwitting rivals in a war to claim the title of Emperor in this richly imagined, Asian-inspired fantasy for fans of Renée Ahdieh and Sabaa Tahir.

Sisters Lu and Min have always known their places as the princesses of the Empire of the First Flame: assertive Lu will be named her father's heir and become the dynasty's first female ruler, while timid Min will lead a quiet life in Lu's shadow. Until their father names their male cousin Set his heir instead, sending ripples through the realm and throwing both girls' lives into utter chaos.

Determined to reclaim her birthright, Lu has no choice but to go on the run, leaving Min to face the volatile court alone. Lu soon crosses paths with Nokhai, the lone, unlikely survivor of the Ashina, a clan of nomadic wolf shapeshifters. Nok never learned to shift--or to trust the empire that killed his family--but working with the princess might be the only way to unlock his true power.

As Lu and Nok form a shaky alliance, Min's own hidden power awakens, a forbidden, deadly magic that could secure Set's reign . . . or allow her to claim the throne herself. But there can only be one emperor, and the sisters' greatest enemy could very well turn out to be each other.

This sweeping fantasy set against a world of buried ancient magic and political intrigue weaves an unforgettable story of ambition, betrayal, and sacrifice.