4 results
I'm Marrying the Pauper Count of a Remote Frontier, So I'll Work Hard to Reform his Territory ~The Letter From Boule~
Henkyou no Binbou Hakushaku ni Totsugu Koto ni Natta no de Ryouchi Kaikaku ni Hagemimasu· 辺境の貧乏伯爵に嫁ぐことになったので領地改革に励みます
manga

Falsely accused of a crime she didn't commit, Angelique is cast aside by the second prince. The cherry on top? Now she has to marry a poor count in a remote parcel of the kingdom. What she finds there is shocking: abject poverty and a strikingly handsome count?! (Source: MangaPlaza)

Henkyou no Binbou Hakushaku ni Totsugu Koto ni Natta no de Ryouchi Kaikaku ni Hagemimasu
辺境の貧乏伯爵に嫁ぐことになったので領地改革に励みます
novel

Angelique's engagement was annulled by the second prince for the crime that she did not commit. Furthermore, by the order of the king, she will be married to the impoverished Count Sergei, who lives in a remote region. What awaits her on her way to the frontier is a very poor estate beyond her imagination and a handsome count! (Source: Earth Star Entertainment, translated)

The Broken Engagement Was Your Own Fault
Konyaku Haki wa Jigoujitoku: Uraomote ga Ari Sugiru Imouto wa Boro wo Dashite Jimetsu shi, Watashi ni Kouun ga Maikomimashita· 婚約破棄は自業自得 ~裏表がありすぎる妹はボロを出して自滅し、私に幸運が舞い込みました~
manga

A fateful turning point arrives for a pair of twin duchess sisters—one earnest, the other arrogant—in this enchanting romantic fantasy set in another world. Sylvie and Annette were born into nobility and renowned as beautiful twin sisters. But while the older sister Sylvie is graceful and upright, her younger twin Annette hides a haughty nature—deriving satisfaction from looking down on others, even Sylvie herself. “I want to be engaged to someone everyone envies…” So when Crown Prince Gerald returns from studying abroad, Annette seizes the chance to approach him, eventually securing a position as his fiancée. Fed up with her sister’s conceit and obsession with status, Sylvie watches from the sidelines—until a misunderstanding on Gerald’s part puts Annette in a serious bind… This is the story of a younger sister consumed by her need for validation and the older sister who forges her own path to happiness through strength and grace https://www.cmoa.jp/title/326793/

Konyaku Haki wa Jigoujitoku: Uraomote ga Ari Sugiru Imouto wa Boro wo Dashite Jimetsu shi, Watashi ni Kouun ga Maikomimashita
婚約破棄は自業自得 ~裏表がありすぎる妹はボロを出して自滅し、私に幸運が舞い込みました~
novel