TV-Series
Description
Kōhei Nikaidō is a private first class in the Imperial Japanese Army's Seventh Division. He is the older twin brother of Yōhei Nikaidō, and the two are nearly identical in appearance and temperament. His background includes service in the Russo-Japanese War, where he fought in battles such as the Siege of Port Arthur alongside his brother.
Personality-wise, Kōhei is obsessive, volatile, and driven by a single-minded desire for revenge. He is highly aggressive and prone to irrational outbursts, but also displays a childish, almost infantile demeanor as his mental state deteriorates over the course of the story. He is deeply dependent on others, first on his twin brother and later on substances and artificial body parts.
His primary motivation is vengeance against Saichi Sugimoto, who killed his brother Yōhei when the twins attempted to murder Sugimoto while he was in custody. This revenge quest consumes him, and he becomes indifferent to the larger gold hunt, caring only about killing Sugimoto. He also seeks to return to his hometown of Shizuoka, but this desire is overshadowed by his fixation on revenge.
In the story, he serves as a recurring antagonist to Sugimoto, frequently appearing to attack him and getting maimed in the process. He initially works under Lieutenant Tokushirō Tsurumi, but his actions are mostly self-serving. His role is both a source of dark comedy through his escalating injuries and a tragic figure whose humanity erodes.
Key relationships include his twin brother Yōhei, whose death defines his entire character arc. He shares a complicated bond with Tsurumi, who uses him as a tool but also punishes him. He becomes briefly allied with Hyakunosuke Ogata during a mutiny. His interactions with Sugimoto are purely hostile. He also develops a bizarre attachment to a human-skin headpiece made by the taxidermist Edogai, which he treats as a surrogate for his brother.
Development: Following his brother's death, Kōhei loses his left ear to a bear attack and has his right ear cut off by Tsurumi as punishment. He later loses his right foot in a fight with Toshizō Hijikata and his right hand in a fight with Sugimoto. He becomes addicted to morphine during treatment, which causes him to regress mentally. He eventually receives prosthetic limbs and a headgear from Edogai, both incorporating weapons. He descends into methamphetamine addiction and psychosis. In the final season, he participates in the climax at Goryōkaku, where he attacks Sugimoto with explosives. He is cut in half during the attack, and in his dying moments, he mistakes his own severed half for his brother, calling out to him as they both perish.
Notable abilities: Kōhei is not a particularly skilled fighter, but he is tenacious and willing to endure extreme pain. He uses trick weapons hidden in his prosthetics, such as a blade in his artificial foot and a gun in his hand. His most notable trait is his inability to stay dead or incapacitated, always returning despite grievous wounds.
Personality-wise, Kōhei is obsessive, volatile, and driven by a single-minded desire for revenge. He is highly aggressive and prone to irrational outbursts, but also displays a childish, almost infantile demeanor as his mental state deteriorates over the course of the story. He is deeply dependent on others, first on his twin brother and later on substances and artificial body parts.
His primary motivation is vengeance against Saichi Sugimoto, who killed his brother Yōhei when the twins attempted to murder Sugimoto while he was in custody. This revenge quest consumes him, and he becomes indifferent to the larger gold hunt, caring only about killing Sugimoto. He also seeks to return to his hometown of Shizuoka, but this desire is overshadowed by his fixation on revenge.
In the story, he serves as a recurring antagonist to Sugimoto, frequently appearing to attack him and getting maimed in the process. He initially works under Lieutenant Tokushirō Tsurumi, but his actions are mostly self-serving. His role is both a source of dark comedy through his escalating injuries and a tragic figure whose humanity erodes.
Key relationships include his twin brother Yōhei, whose death defines his entire character arc. He shares a complicated bond with Tsurumi, who uses him as a tool but also punishes him. He becomes briefly allied with Hyakunosuke Ogata during a mutiny. His interactions with Sugimoto are purely hostile. He also develops a bizarre attachment to a human-skin headpiece made by the taxidermist Edogai, which he treats as a surrogate for his brother.
Development: Following his brother's death, Kōhei loses his left ear to a bear attack and has his right ear cut off by Tsurumi as punishment. He later loses his right foot in a fight with Toshizō Hijikata and his right hand in a fight with Sugimoto. He becomes addicted to morphine during treatment, which causes him to regress mentally. He eventually receives prosthetic limbs and a headgear from Edogai, both incorporating weapons. He descends into methamphetamine addiction and psychosis. In the final season, he participates in the climax at Goryōkaku, where he attacks Sugimoto with explosives. He is cut in half during the attack, and in his dying moments, he mistakes his own severed half for his brother, calling out to him as they both perish.
Notable abilities: Kōhei is not a particularly skilled fighter, but he is tenacious and willing to endure extreme pain. He uses trick weapons hidden in his prosthetics, such as a blade in his artificial foot and a gun in his hand. His most notable trait is his inability to stay dead or incapacitated, always returning despite grievous wounds.