The Imposter Bride: The Manipulated Damsel Is Cherished by the Coldhearted Duke

"You will go in place of my daughter to be wed to the Duke of House Dubarry." Leonora has been working tirelessly to ensure her family is fed and out of harm's way. One day, however, she is kidnapped and brought before the notorious Duchess Godot who has one strong demand: pose as her daughter Angennia to be married into the rival house Dubarry, and spy on the Duke for her. Leonora can't refuse, as House Godot now holds her family hostage. Though there are many rumors of the Duke of House Dubarry being a cold and menacing man... Leonora finds herself before a kind and charming gentleman with nothing but warmth! It may be impossible to keep her identity a secret before the wonderfully kind Dinando Dubarry...!!

(Source: MangaPlaza)