Gunma  

Gunma, also known as Dr. Takamatsu's raised scientist, exhibits childishness and eccentricity with a slight obsession for inventions resembling swans. Initially, he believed his father to be Luzar but later discovered it was Magic. Despite being Magics eldest son in terms of birth order, after the revelation that he and Shintaro were switched at birth, Gunma is Kotaros biological brother.