The Royal Thief (Thorin/OC)

Nyssa is a thief traveling through Mirkwood when she was captured by King Thranduil's guards. In order to earn her freedom, she is tasked with stealing the Arkenstone out of the Lonely Mountain. But, the Arkenstone is taken by another, and Nyssa is blamed for the theft. She escapes, and the dwarves are in pursuit, especially a certain dwarf king, Thorin, who is angry that he is taken for a fool. It's a cat and mouse game with Nyssa running across the lands of Middle Earth trying to prove her innocence. For she broke her one cardinal rule. She fell in love with the mark.