Шінодзука Кен

Franken is the leader of a gang of delinquents at Rihito's school, and the older brother of Aoi. He uses a screw as an earring, which lead to his nickname. He is willing to fight others for the sake of his juniors, and despite being a delinquent he has never used cigarettes or alcohol. Ranmaru quickly recognizes him as a virgin.