Shirosuke Inudou served as the warden of Abashiri Prison. His gaunt face featured furrowed eyes, no eyebrows, a thick nose, light hair forming a widow's peak, and a dark mustache with a heavy beard. He typically wore a high-ranking military uniform.

Inudou was known as the "Demon Warden" for his cruel and merciless treatment of prisoners. He forbade old friends from meeting inside the prison and held a deep grudge against the Shinsengumi, particularly Toshizou Hijikata, due to his elder brother's death at their hands. His desire for revenge drove him to wish for Hijikata's spirit to break before execution. Inudou regarded Abashiri Prison as his personal domain, where he exercised absolute authority. He showed no tolerance for traitors and employed brutal methods to eliminate them.

Shinpachi Nagakura once visited Inudou after seeing Hijikata imprisoned in Kabato and requested to meet his old friend. Inudou refused, and when Nagakura attempted to harm him, Inudou became enraged and had guards expel him. Later that year, Inudou was transferred to Abashiri Prison as warden and moved Hijikata there to monitor him closely. When head jailer Kadokura reported a spy for the 7th Division among the guards, Inudou ordered Kadokura to have the new guard killed by any means. He declared that anyone who opposed him could become fertilizer for the prison farm.

Inudou confronted Hijikata in a duel, during which he was severely wounded and ultimately decapitated by Hijikata.

The character may have drawn inspiration from two historical figures: Tsukigata Kiyoshi, the first warden of Kabato Prison, and Arima Shirosuke, the first warden of Abashiri Prison, who was known as the "Monster Warden" for his merciless treatment of prisoners.