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Kurozumi Kanjuro is a samurai of Wano in the world of One Piece. A member of The Nine Red Scabbards, who were the retainers of Kozuki Oden. Kanjuro is, in fact, a member of the Kurozumi Family and has been serving as a spy for Shogun Orochi since the beginning.
Like Orochi, the persecution of his family has made Kanjuro a twisted man with a similarly demented disposition, however, he lacks the perverse sense of revenge against the people of Wano that Orochi enforces under his rule, and instead is apathetic. Instead, Orochi describes Kanjuro as "having no heart" and indeed similar to the Vinsmoke Brothers (who were also described in a similar manner) Kanjuro lacks empathy and sympathy.
Befitting his appearance resembling traditional Japanese Kabuki performers and his own upbringing within a theater Kanjuro is a brilliant actor whose dedication was unmatched by even CP9's extensive undercover work in Water 7. Playing the role of a dedicated servant to Kozuki Oden while secretly passing off and sending information to Orochi for years without raising suspicion. Oden scoffed at the notion of there being a traitor among his retainers and even after the Samurai were left with no other choice but to realize that they had a mole none suspected Kanjuro until he himself revealed it. Kanjuro is very dedicated to playing his role to the utmost perfection and was willing to die as a Kozuki Clan retainer alongside Oden and the other Scabbards, and in fact, has longed for a place to die since he was very young.
When the Scabbards were on their way to Onigashima to confront Kaido, Kanjuro revealed himself to them in a dramatic manner. He admits that he does not mean any harm but wanted to act out his role. While revealing himself as the traitor, Kanjuro was unapologetic and happy to see the baffled looks on their faces. Although he himself claims that he never hated any of them, he was clearly proud of his role.
However with Kanjuro's pride in his acting also comes great rage when he finds that things did not go as intended such as when Luffy, Kid, and Law appeared at Port Tokage to aid the Scabbards, and when Denjiro revealed that they had been misled by the luck of Kinemon failing to notice an alternate way to interpret Yasuie's instructions on the secret code card.
Nine Red Scabbards: Kanjuro has been a retainer of the Kozuki family for no less than 21 years of his life meeting Oden at age 18 and not exposing himself until he was 39, factoring in being sent 20 years into the future and Kanjuro's deception is 41 years old for those who did not travel into the future, Denjiro, Kawamatsu and Ashura Doji.
Before his true allegiance was revealed, Kin'emon showed great care towards his comrade and wanted to save him in Dressrosa and the reason that he had been captured was that he had sacrificed himself so that Kin'emon could go after and rescue Mononosuke. However, the fact that Kanjuro failed to pick up that Kinemon had simply gotten lucky and misread the instructions when the other Nine Red Scabbards could (similarly to how Blackbeard couldn't place Luffy as being Ace's brother while the commanders of the Whitebeard Pirates could) shows his own ignorance about the people that he'd spent years of his life with. He fought and lost against Kikunojo.
Kozuki Family: Kanjuro himself had no problems with kidnapping Oden's son, Momonosuke, and would go onto mock and belittle the boy for his inability to lead and for amounting to nothing but a hostage for Orochi and Kaido. He also stated his intentions of killing the still living Hyori, a hypocritical statement to not wanting to harm them.
Abilities and Powers
As a Samurai retainer of Kozuki Oden and a member of the renowned Nine Red Scabbards, Kanjuro is a strong samurai who is treated as a legend in Wano. The Shogun of Wano, Orochi who has the backing of Kaido, takes the Nine Red Scabbards and their continued existence as the most potent threats to his rule when he previously dismissed CP0 as nothing to his governance with Kaido's backing.
While Kinemon initially implied that Kawamatsu, Ashura-Doji, and Denjiro were stronger than the other scabbards, Kanjuro was shown to be capable of clashing and repelling Kawamatsu using his oversized brush against Kawamatsu's sword. This moment indicates that he was hiding the full extent of his abilities all this time, as the uses of his Devil Fruit and physical abilities and tactics were far above what Kanjuro ever showed as a Scabbard.