An underling of Fumiya’s (and therefore a Kyokuto student), Yoshiaki is beaten when the Oni-Baku take Fumiya down. He appears in the next volume under the control of Okubo, and is a reluctant pawn because Okubo kidnaps his girlfriend Natsumi. He turns on Okubo and helps Onizuka by getting Ryuji and the Oni-Baku-gumi to come to his aid (he was already suffering a broken foot, which had him at something of a disadvantage against an entire gang of armed punks). He appears after these events with Natsumi, and they appear to have returned to life as normal, and is seen during the Midnight Angels conflict causing problems for the police with his gang. Wikipedia