To Seduce a Lady by Jenn Langston

Damien Serra, Marquis of Reston, chose his bride four years ago to end a feud between his estate and the adjoining barony. Making one final trip to her family’s estate in the country, he is ready to collect his bride. Unfortunately, she refuses a quick marriage due to a desire to enjoy London society before she becomes betrothed. Although reluctant, Damien agrees. However, the delay gives him an opportunity to spend more time with the lady’s sister. To his astonishment Miss Madison Parker captivates his attention far more than that of her sister.
Madison Parker is surprised to discover how much she enjoys being in the company of her sister’s intended. She had known Damien for years with his frequent visits and she’d never been tempted by him. But something about him now is different. With the betrothal on hold, she finds no harm in sharing a few rides about the grounds with the marquis as well as a few stolen kisses.
Watching Madison pursued by other men in London proves to be far more difficult than Damien expected. He couldn’t go back on his promise to her sister, but how could he marry a girl when his thoughts were filled with nothing but Madison?