Childhood friend of Jean, he has been his friend at least since hig school, he takes picture for some journal and sometimes keeps company to Jean and his sister since he is well known to the brothers.

Spoiler: He is the son of a man that is subordinate to the royal family, at very little age, he and his father abandoned their old lives to look over the princess who gave up royalty to see the world with that man, preventing his father of abandoning him to protectfrom that mission and live his life as his own, what diddn't happened, he is one of the few ones that knew that Jean had real blood from the start, observing his relation to the coup from the background until telling him himself. He could go to school with Jean despite being much older than him by faking his age using only glasses. His real name is never revealed, Niino is the name he got in the new life and his father died in the same train accident that Jean's parents did.

(Source: Wiki)