Kozuki Oden

Yamato is the son of Kaidou. Born as Kaidou's daughter and groomed from a young age to be his heir, Yamato instead developed a profound admiration for the legendary samurai Kouzuki Oden. After Oden's death, Yamato decided to become like him, impersonating him and adopting his mannerisms. As a result of this desire to emulate Oden, Yamato decided to become a man and identify as Kaidou's son, with his father and the Beasts Pirates referring to him as such as well.

Being assigned female at birth and not usually choosing to explicitly present as male, Yamato has typically been referred to as a woman by people when they first encounter him.Yamato is taller than an average human, standing at 263 cm (8'8"). He has long, white hair that is bound between orange rods into a ponytail at the back, which fades into aqua green and then blue the further down it goes, and ends in rectangular locks similar to Kaidou. Yamato also has large, orange eyes with prominent eyelashes, wears gold hoop earrings on both ears, and has horns on the top of his head which are mostly red, but gradually become more flesh-colored toward the base. Yamato's current outfit is a sleeveless white garment with a diamond-shaped design on both sides and an indigo, wisp-patterned bottom half. He wears a pair of red hakama pants and sandals, and, much like Oden, wears a large purple and white nio-dasuki behind his back. While in disguise, Yamato originally also wore a hannya mask, which has a blue wig with an extremely long and wild mane attached to the top and a long blue goatee attached to the bottom.The kimono initially had long white sleeves, but were ripped off along with the rest of the disguise making Yamato's kimono more form-fitting.

Yamato greatly admires the legendary samurai Kouzuki Oden to the point of even proclaiming to carry his identity. Yamato has self-identified as Oden on multiple occasions and has even emulated his gender, proclaiming to be the son of Kaidou due to Oden being a man. Although initially carrying doubts as to how to present as Oden, Yamato has steadily expressed a straightforward attitude regarding this identity as time has gone on, even proclaiming this as such to Oden's son Momonosuke, to the boy's horror.Although having wholeheartedly embraced this identity, Yamato retains his original persona, referring to Yamato as his "other name". Yamato does not seem to like being misnamed, having quickly corrected Luffy when given a nickname.

Having read of the great exploits documented by Oden in his logbook, which he considers his "bible", Yamato dreams of leaving Wano Country's confines and setting out to sea with the Straw Hat Pirates, much like Oden did with the Whitebeard and Roger Pirates decades before. Yamato also wishes to fulfill the goals that Oden had, namely opening Wano's borders, in direct defiance to Kaidou's wishes for the country. Yamato has shown to be extremely strong-willed, having put up considerable resistance to Kaidou's imprisonment despite taking decades to finally break free. Although initially seeming to be more subordinate to him previously, Yamato's battle with Ace led to him destroying Kaidou's dragon statue in an act of defiance that has since led to more outright rebellion. Yamato has engaged in combat with Kaidou numerous times and has openly expressed opposition and defiance to his plans concerning the two of them, accompanied by insults. When the Ninja-Pirate-Mink-Samurai Alliance invaded Onigashima, Yamato was immediately willing to help them and had no qualms with attacking members of his father's crew, making his intentions and loyalty clear to them in the process. Yamato is also willing to go to great lengths to achieve his objectives, having basically kidnapped Luffy in order to get to talk to him and following through with this tactic even after Luffy responded by fighting back.

Yamato is more than willing to put his body and life on the line to protect people out of care, believing that Oden would never abandon a comrade in danger. Yamato resolutely withstood a barrage of powerful artillery strikes by the Armored Division to protect Momonosuke and later confronted Kaidou alone to stall him until Luffy returned despite knowing he was no match for his father. However, Yamato also takes enjoyment in engaging in combat; despite framing his plan to split up from Momonosuke as a decoy strategy to trick the Beasts Pirates, Momonosuke and Shinobu both noted to themselves that he seemed mainly interested in going to fight.