Rescued by the Duke (Dukes, Spies and Lies book 1)

The war is over, and the former spymaster must return home and take up the reins of the dukedom his father left in shambles. But that's not the worst of his problems. He must also secure a wife. And the last thing Duke Erembour needs is to fall in love with the headstrong sister of his rival. Especially not with her. She’s the worst possible choice, even if she's the only woman he wants.

Lady Aurora may be the sister of a duke with the dowry to match, but a clause in her father’s will has given her the chance to choose her future. And she has no intention of settling for any of the pretty but useless young bucks vying for her hand. Nor does she have any intention of losing her heart to her brother’s dark and secretive rival, no matter how brilliant that rival may be. She wants love, which is the last thing the powerful and reclusive Duke Erembour is offering her, and the only thing that will convince her to marry him. When Lady Aurora accidentally uncovers one of Duke Erembour's greatest secrets, a mysterious group will stop at nothing to wrest it from her and silence her forever. Duke Erembour knew he wouldn’t escape the war unscathed, but he never expected this. Now his only chance is to trust Lady Aurora with everything, including his heart. It’s a terrible bargain. If only the alternative wasn’t so much worse.