Daisy, the elder sister, had barely breathed a sigh of relief upon the engagement of her younger sister Margaret to the Duke, when,

to her shock, Margaret became pregnant after a casual encounter, even before the formal betrothal.

"I want to have the baby, but I also want to marry the Duke," her younger sister selfishly declared.

To grant her wish, Daisy is ordered by her parents to take Margaret's place and marry into the Duke's family, pretending to be her sister for the entire duration of the pregnancy and secret delivery.

Daisy had been optimistic, thinking she could surely deceive the Duke, who was famous for being handsome but reclusive and disliked people.

However, for some reason, the Duke actively pursued her from their very first day together...