Never Deny a Duke by Madeline Hunter

He is the last duke standing
. . . the sole remaining bachelor of the three self-proclaimed Decadent Dukes. Yet Davina MacCallum’s reasons for searching out the handsome Duke of Brentworth have nothing to do with marriage. Scottish lands were unfairly confiscated from her family by the Crown and given to his. A reasonable man with vast holdings can surely part with one trivial estate, especially when Davina intends to put it to good use. Brentworth, however, is as difficult to persuade as he is to resist.
The Duke of Brentworth’s discretion and steely control make him an enigma even to his best friends. Women especially find him inscrutable and unapproachable—but also compellingly magnetic. So when Davina MacCallum shows no signs of being even mildly impressed by him, he is intrigued. Until he learns that her mission in London involves claims against his estate. Soon the two of them are engaged in a contest that allows no compromise. When duty and desire collide, the best laid plans are about to take a scandalous turn—into the very heart of passion . . .