The second daughter of Viscount Fahrenheit, Clarisse, has lived her entire life in the shadow of her beautiful older sister, Matilda, enduring cruel treatment from her own family. At nineteen years old, her father arranges for her to marry Margrave Jean Gutenberg, a powerful frontier lord known as the Man-eating Margrave for his odd and fearsome personality. Having asked the King for the Jewel of Fahrenheit as a reward for his victories in war, the margrave expects Matilda as his bride, but Clarisse’s parents send her instead as a counterfeit substitute.

Though Clarisse is almost relieved to escape her miserable home life, she lives in constant fear that the margrave will discover the deception. Upon arriving at his domain, however, she is surprised to find that he is not the cruel man of rumor but rather a thoughtful and handsome nobleman. As she begins to enjoy her days with him, it becomes clear that the clumsy margrave is growing genuinely fond of her, and he starts to dote on the unfortunate bride he received by chance. Just as Clarisse starts to believe she may have found true love and happiness far from her family, the day arrives when a hidden family secret is finally revealed, threatening to shatter the fragile trust between the counterfeit bride and her fateful husband.