Guys, help me find a manga in which the parents were executed by the Imperials, and the twins had blonde hair with green eyes, and had magical powers that needed to be concealed or the Imperials would find them. After growing a bit, the girl went into medicals while the boy became a knight and changed his identity by changing his hair color to brown, and the girl kept her original style identity with blonde hair and green eyes. And the girl was doing some medical experiments and got into the Duke's castle, and the Duke was some head or the king of magical beasts.the duke had blue hair please find me this i can't find it anywhere else
