The Court of Stars (The Commonwealth Quartet) (Volume 1)

The universe is bigger and stranger than Christian Arundel could ever have imagined- and right now, almost everything in it is trying to kill him. On the eve of Christian's betrothal to a woman he doesn't love, the castle where he lives is attacked by a force of demons from the sky. When he tries to fight against them, he's taken prisoner. One of their other prisoners, a sarcastic miniature dragon named Miriet, agrees to help him escape. Christian must learn how to use the demons' weapons to escape their clutches, but that's only the beginning. To rescue the people he loves, he must cross half the world and return to the invaders' ship.