Earl of Charm by Maggie Dallen

The Earl of Charm has it all—the title, the wealth, the land. The only one thing he doesn’t have? Charm.
As the second son, Alexander Gordon was never supposed to inherit the earldom. But then again, his elder brother wasn’t supposed to die in a tragic hunting accident, either. Alex’s gruff manners and quiet nature are far better suited to his solitary life as as a scholar, but Alex is honor-bound to do right by the title and by his family. Which means…he must find a wife. More importantly, he must learn how to woo a wife.
Luckily for Alex, his great aunt has brought her companion along to celebrate Christmastide. The lovely Miss Lovelace might be plagued by scandal and notoriety, thanks to her family’s downfall, but she knows more than anyone about the art of charm and flirtation. His new instructor makes the ideal practice partner for conversation, and dancing, and…kissing? But no, that was a mistake. He has a duty to his family to uphold, and as delectable as his new teacher might be, she’s not a proper choice to be his wife. When it comes to love versus duty, it would be wicked to choose with his heart…wouldn’t it?