Before being sent to prison, Kitamakura was a sumo wrestler, and his immense size and strength are a direct remnant of that past. His name, written with characters that refer to the traditional way a deceased person's body is laid out, hints at his role as one who brings death. Within the walls of Kokubu Prison, he holds the title of one of the Four Emperors, a group of enforcers who rule the inmate population on behalf of the Warden and Administrator Sugiyama. As the leader of the East cell block, Kitamakura is a major antagonist and a powerful obstacle for the protagonist, Riki-Oh.

His personality is defined by a raw ambition and a hunger for power. While loyal to the prison administration, he holds no genuine allegiance to his fellow enforcers. He views the other Emperors, Yomi and Shiragami, as rivals to be eliminated so that he can become the sole ruler under the Warden. This self-serving nature makes him unpredictable; he is just as likely to attack an ally as an enemy if it serves his goal of gaining more control. He also possesses a warrior's pride and a desire to test himself against strong opponents, which draws him to fight Riki-Oh.

Kitamakura's role in the story is that of a secondary antagonist who shifts between being a direct threat and a temporary, unwilling ally. He is first seen crushing a prisoner's head with his bare hand to quell a budding riot, instantly establishing his brutal reputation. During Riki-Oh's fight with Yomi and Shiragami, Kitamakura interferes not to help them, but to advance his own position, throwing a pitchfork that impales Shiragami. When a wave of quick-drying cement floods the area, he is saved from drowning by Riki-Oh, who assumes this betrayal signals an alliance. This act of mercy does not change Kitamakura's ultimate goal. Later, he confronts Riki-Oh in a prison cell, revealing his plan to kill the other Emperors and become the top enforcer. After a brutal fight, Riki-Oh defeats him, severing one of his hands and leaving him for dead.

The character undergoes a significant, if tragic, development in his final moments. When the Warden activates a device to lower the cell's ceiling and crush Riki-Oh, the dying Kitamakura is also trapped. He pleads for his life, only to be callously discarded by Sugiyama, who declares him useless now that he is defeated. In a final act of redemption and defiance, Kitamakura uses the last of his strength to hold up the ceiling, sacrificing himself to save Riki-Oh. As he dies, he drops a photograph of himself with his mother from his sumo days, revealing a hidden humanity and a past life he still cherished.

Kitamakura's abilities are directly tied to his former career as a sumo wrestler. He is a giant of a man with tremendous physical strength, capable of crushing a human skull with a single hand. He is a formidable hand-to-hand combatant, using his massive frame to deliver crushing blows and restrain his opponents. In the English dub of the live-action film adaptation, he is known as Tarzan.