To Captivate the Viscount by Aileen Fish

Revenge is a dish best-served cold… Or is it? These wallflowers are about to find out, as they plot against those most deserving. Can society handle a wallflower’s revenge? Or will their targets topple one by one?

CeCe Dixon is tired of being overlooked, and when the militia arrives at the nearby training camp, she decides to set an example for her younger sisters and find herself a husband. She won’t settle for just any husband, either, he must be kind, handsome, and madly in love with her.
Justin, Viscount Stavely, is at first flattered by Cece’s flirtations, and soon finds himself under her spell. He’s falling quickly—until one night he finds her in a passionate embrace with another man. Rather than let his fellow soldiers know how deeply he’s hurt, he withdraws from the many social activities in the nearby town.
CeCe is devastated that Stavely would believe her capable of such an indiscretion, and when she learns someone deliberately mislead the viscount, she vows revenge. Nothing will stop her from discovering who did this and disgracing him somehow.
And nothing will stop her from convincing Stavely she loves only him, and his best future will be with her at his side.