Cruel Beauty [Cruel Beauty #1] by Rosamund Hodge

The romance of Beauty and the Beast meets the adventure of Graceling in a dazzling fantasy novel about our deepest desires and their power to change our destiny.

Betrothed to the evil ruler of her kingdom, Nyx has always known her fate was to marry him, kill him, and free her people from his tyranny.

But on her seventeenth birthday, when she moves into his castle high on the kingdom's mountaintop, nothing is as she expected—particularly her charming and beguiling new husband.