"I'm going to marry the most beautiful woman in the country" declares the crown prince, and Miriage (Milliage), a poor baroness, is chosen as one of the candidates for the crown prince's wife because of her beauty. If such a person becomes king, the country will be destroyed! Feeling a sense of crisis, Miriage embarks on a reform of her domain to protect her people. Amidst the difficulties ahead, she falls in love with a man other than the crown prince.... This encounter leads to an unexpected situation (⁉)-a story of an impoverished baroness's struggle to reform her domain! 「国一番の美人と婚約しようと思う」皇太子の宣言により、貧乏男爵令嬢なのに、その美貌で皇太子妃候補の一人に選ばれてしまったミリアージュ。「こんな人が王様になったら、国が滅んでしまう！」危機感を感じたミリアージュは、領民を守るため領地改革に乗り出す。前途多難な中、皇太子以外の男性に恋をして…。この出会いが思いもよらない事態をもたらす（!?）貧乏男爵令嬢の領地改革奮闘記、第1巻！