When Deacon got his first look at Camila, his universe changed. When he saw the threat against her, he knew he'd have to do whatever it took to protect her. Even if that meant marriage. After he took care of the threats against her his fear of losing her made him crazy. He just knew he'd do whatever it took to keep her with him.
Camila had no idea the people she was supposed to trust the most were the ones out to destroy her. She'd been secluded so long she had no idea how to fight back. When Deacon came to her rescue, she was relieved and then shocked when he told her the only way to protect her was to marry him.
She didn't know if she could give a man she'd never even talked to the power to control her world. She just had to decide which situation was best for her. Marry a man she didn't know or stay with the family that was ready to betray her.