Harstairs House:

From the author of Mr. Knightley's Diary and Lord Deverill's Secret comes a sparkling tale of a woman, her inheritance, and the rake who could ruin everything. Inheriting a house from a stranger was shocking enough. Then Susannah Thorpe learns that in order to claim her inheritance, she must either wed in a month, or else spend the next thirty days in Harstairs House-a place purported to be haunted. Not about to marry, she makes the arduous journey to her new home, only to discover that there's already a tenant living there: a broodingly handsome man named Oliver Bristow, who has no intention of leaving before his lease runs out-in another month. Now Susannah must share her quarters with her mysterious, rakish tenant- without falling head over heels in love.