The Dragon's Bride.

Forced into a strange world and learning that she ”beloved” princess, Miriam is thrown into a marriage for political ”alliance”. Her new groom is rumored to be a cruel, evil king, and the last of the Dragonkind, King Vincent Darkimir, also known as the Dragon. When her father, King Alaric, assigns her to kill the Dragon if not her mortal family will pay. But can she really bring herself to kill someone? Even if they are as evil as they are said to be? Or will she sacrifice her family for him?