Eloise is sent as a substitute bride for her half-sister, destined to marry the fearsome Duke Tristan, a renowned warmonger and the conqueror of their enemies. With an imperial command to seduce and uncover his vulnerabilities, Eloise steps into a perilous game. But on their very first night, her disguise is shattered. Just as she braces for the worst, the Duke surprises her with a chilling command: "Get on the bed. As the substitute bride, you must fulfill your role." To survive, Eloise surrenders to the Duke's demands, finding herself irresistibly drawn into a web of dangerous desires. Will she navigate this treacherous path, or lose herself in the passion that binds her to the Duke?