This book reminds me of why I love Eloisa James as an author!Olivia, introduced to us in the novella "Winning the Wallflower" (friend of the wallflower, Lucy) is engaged to be married to a duke-to-be, currently a marquess. But Rupert is not only 5 years younger than Olivia, he's... not quite all there. At birth, Rupert lacked oxygen, and his brain functions in a very different way than "normal".Problem is, Olivia's father and Rupert's father were schoolchums and determined before either was even married that their children would be betrothed. So poor Olivia has been betrothed since birth. She likes Rupert, but she's embarrassed by him.However, her mother has spent her entire life modeling Olivia into the perfect little duchess... Olivia and her twin, Georgiana. Georgiana is everything that Olivia is not: tall, slim with the fashionable figure, and dignified. Georgiana is, in short, the perfect duchess. Olivia sees herself as short, fat, and obstinate; among her favorite past-times is reciting bawdy limericks and sneering at her mother's oft-quoted duchess bible, "The Mirror of Compliments" written by the Duchess of Sconce.When it comes time to wed Rupert, however, Rupert has other plans. He's decided that he wants to contribute to his family's history of glory on the battlefield, and Rupert is determined to lead a company of men in the French war against Napoleon. Rupert's father has no choice but to enable his son in the only way he knows how: give him a company of 100 men that no one else wants and ship him to Portugal, away from the action. But before Rupert leaves, his father wants to secure a chance at a future, and he "commands" Rupert and Olivia to "do the deed", promising to make a future of Olivia should she become pregnant, even if Rupert somehow dies in battle.In one of the most touching and funny scenes of the book, Rupert and Olivia attempt to put their limited knowledge of how "the deed" works into action. But poor Rupert is limp like celery; so Olivia promises never to tell, and the two keep up their fictional encounter as Rupert ships out. But because Olivia might be pregnant (or so Rupert's father thinks), her family sends her off with Georgiana, who's been invited by none other than the Dowager Duchess of Sconce to become part of the dowager's "tests" to see if Georgiana is the perfect duchess for her son, Tarquin (Quin).Tarquin is mathematical and logical, but he's not attuned to emotions; one could almost argue for him to have a touch of Asperger's syndrome, except IMO, Quin is simply surrounded by logic and not encouraged to be emotional. Thus he has no familiarity with emotion - none but painful, that is. Quin was married to Evangeline, a most unsuitable woman for a duchess, but he fell madly in love with her beauty and her life; except that Evangeline thrived upon emotion and demanded pretty words and emotions from Quin that he couldn't provide. So Evangeline sought them from any and all other men, publicly cuckholding Quin. She died with her lover, rowing out to a boat to take them to France; as Quin watched the boat go down, he jumped into the sea to try to rescue them, but he almost drowned.So on a dark and stormy night after the house was all abed, Quin is roused by insistent knocking at the front door. Upon answering it, his senses are assaulted by a very wet, very passionate Olivia, demanding help for her sister, their chaperone, and their groom. Seems they had a carriage accident some way from the house, and Olivia volunteered to get help. But Quin can't take his eyes from Olivia - there's a spark in her that flames his own unused heart to life.While his mother focuses on Georgiana as part of her tests for the perfect duchess, she loathes her sister, Olivia. But knowing that Olivia is engaged, she decides that Quin can safely entertain Olivia, thus getting Olivia out of the way, so that the dowager can determine the perfect duchess for Quin. But, of course, Fate has other plans for Quin's and Olivia's hearts.When Rupert's father, the duke, charges in telling all of Rupert's fame and glory in battle, Quin is afraid he's lost Olivia forever. How can he compete with a man who understands emotion and poetry, and who's now a national hero? Olivia, too, is torn between her promise to Rupert and caring for him -- she's just not in love with Rupert. She's given her heart, body, and soul to Quin. But now what?When word reaches them that Rupert is deathly ill but trapped on the shores of France, Olivia is determined to rescue him. But then what? Will Quin assist? Can Olivia find Rupert and get him out safely? And will Quin and Olivia ever be together?======================My favorite scenes take place in trees! And with a half-French cousin modeled after the B-fever pop sensation of today. Lots of wit, lots of realism, especially about relationships - which is tough to find in romantic books, and lots of fun and engaging characters!