A Cinderella story of intrigue and reversal, in which a fallen noblewoman joins forces with a strategic marquis. Mireille, daughter of the prestigious magical Rievel family, loses everything after her father is blamed for an incident. She now works diligently at a diner to earn money for his medical expenses. Her goal is to buy back the pendant that belonged to her late mother, which she had to give up when her family fell from grace. One day, Marquis Leonardo, one of the most prominent men in the royal capital, appears and offers her a place in his mansion—as his formal fiancée. Surrounded by the marquis's devoted affection, Mireille sets out to reclaim the pride and happiness stolen from her.