Synopsis: Junketsu no Dansou Reijou Kishi wa Isai no Shukun ni Ubawareru

I Was Raised as a Man to Be a Knight, Now I Serve a Prince Who Wants My Heart / The Cross-dressing Lady Knight Is Taken with Her Remarkable Lord / 純潔の男装令嬢騎士は偉才の主君に奪われる Noah was raised as a boy since he was born in order to take over as the heir to the Phaistos family. However, he decided to hide the fact that he was actually a woman, left the family for his younger brother's sake, and joined the army.Noah has continued to rack up military achievements in order to become the commander of the federation army, and one day was handpicked to join Prince Johann's bodyguard squad. The prince's bodyguard squad was made up of unique individuals that were the creme of the crop: Noah; his adopted older brother, Kai; the twins Jaden and Benjamin, Dominic, said to be the strongest soldier in the military; and the youngest, Osker. However, Johann often acts like he's not a member of the royal family and is actually a flippant flirt! But as Noah serves Johann, he gradually comes to know how Johann actually feels... https://www.cmoa.jp/title/290781/