Koujaku is a prominent character in the visual novel and anime series DRAMAtical Murder. He is a skilled hairdresser and Aoba's childhood friend, known for his striking appearance with long, dark hair and red tattoos. Koujaku is fiercely protective of Aoba, often acting as his guardian. Despite his tough exterior and involvement with gangs, he is kind-hearted and deeply cares for those close to him. Throughout the series, Koujaku's loyalty and complex past play a significant role in the storyline.