Dean Of Detention is the final boss of Kendo Rage, it was obvious from its lines and mannerism that it was intended to be an evil teacher of some description and its demonic qualities were also fairly blatant. it attacked in several stages, beginning with firing energy-balls.
After the first defeat it morphed into a bizarre form with extremely long arms that emitted spikes and apparently defied the laws of physics via trapping Jo between them in a strange prison.
Following that defeat Dean Of Detention splits into two separate beings and attacks via charging at Jo while also occasionally reverting to his old energy-bolt pattern.