After her mother's death, an abused young countess is forced into a miserable marriage with a gambling addict. Her only escape is her obsessive 'fangirl' devotion to a revered Grand Duke. When her husband eventually sells her off to pay his debts, she collapses in despair—only to wake up transported back in time to age 18. Determined to avoid her tragic fate and protect her inheritance, she uses her extensive knowledge of her idol to propose a fake engagement to the Grand Duke himself, gambling everything to rewrite her destiny.