Saikyou no Kurokishi, Sentou Maid ni Tenshoku shimashita

Fantasy

Albright, who was famous as "the strongest Black Knight," was reincarnated as a girl, Maria, whose ribbon suited her well for same reason. Maria, 16 years old, is currently a maid in the Marquess of Urband family in attendance to the Daughter of the Marquees, Relena. After Relena became engaged to the 4th Prince, the area around Maria had gotten busier... (Source: Gentosha Comics, translated)