Kumagai is one of the inspectors in charge of Shonan Disciplinary School. He replaces Ishihara as the inspector in charge of the Cell 206 after an incident caused by Ishihara.<br /> <br /> Kumagai is very kind and always shows great concern for the boys. He always greets them with a genuine smile. After he replaced Ishihara, the boys started to find a bit of peace in their confined lives.<br /> <br />