Georgette Heyer

Young Kitty Charing stands to inherit a vast fortune from her irascible great-uncle Matthew--provided she marries one of her cousins. Kitty is not wholly adverse to the plan, if the right nephew proposes. Unfortunately, Kitty has set her heart on Jack Westruther, a confirmed rake, who seems to have no inclination to marry her anytime soon. In an effort to make Jack jealous, and to see a little more of the world than her isolated life on her great-uncle's estate has afforded her, Kitty devises a plan. She convinces yet another of her cousins, the honorable Freddy Standen, to pretend to be engaged to her. Her plan would bring her to London on a visit to Freddy's family and (hopefully) render the elusive Mr. Westruther madly jealous. But she didn't count on falling in love with the dandified Freddy.--From http://www.amazon.com.

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