Carabosse and the Spindle Spell by Sylvia Mercedes

Shy but magically talented, Princess Carabosse only wants to help her people as they face the looming threat of the Warlock King and his daughter, Aurora. Aurora was gifted from infancy with fairy blessings that make her the most lethal magic-user the world has seen in centuries . . . and she wants Cara’s kingdom.
The only hope for fighting off this deadly threat is the loyalty of the twelve Dragon Lords. They have sworn allegiance to the Briar Crown. But when the crown falls into Aurora’s clutches, who will the dragons serve?
Armed only with a humble spindle and a gift for spinning magic, Cara alone stands against the Warlock and his daughter. Will she find unexpected help from the twelfth Dragon Lord, handsome shape-shifter Torald? Or will the vows he swore to the Briar Crown force him to turn against Cara and serve the beautiful Aurora?