Botsuraku Reijou, Bimbou Kishi no Maid ni Narimasu

Amongst nobles and royals, Lady Agnes, daughter of an aristocrat is the "Rose Amongst Thorns," due to her unparalleled beauty. On the other hand, Bernard is the fifth son of a Lord who rules a small rural town far from the capital. At first glance, Bernard gets stared down in disgust by Lady Agnes, most likely because of his lowly status. Five years later, Lady Agnes's father faces trial due to embezzlement, resulting in her family losing everything. After receiving the status of a "fallen aristocrat," everyone leaves Agnes to fend for herself... except for Bernard, the low-ranking knight. A misunderstanding develops into a charming love story!

(Source: MangaPlaza)