Dark Dancer - Dark Dancer, #1

Her people wanted a ruler. They may have created a monster. For the Qurl race, being chosen as the next ruler could be a dream come true for the right girl. Or a nightmare for the wrong one. Instead of being given a crown, she must survive a wrenching physical metamorphosis. Unfortunately for Yitzen Tines, war is looming with a powerful adversary. Her people need a warrior, not an accomplished dancer.
And certainly not her.