Appearance
Yorki is a yellow haired pirate who typically wears a cowboy hat. He also has two tattoos on his face. One under his right eye and one under his lower lip. The tattoos resemble that Japanese Kanji (ヨ). He also wears a green captain's coat.
In the anime, prior to his full appearance, he was depicted as a young brown haired tattoo less pirate that wore a tricone instead of the cowboy hat. His coat was also colored red instead of green. This was later changed in accordance to the manga's depiction.
History
Fifty years ago before the current timeline, as Yorki and his crew were sailing the West Blue, they came across a baby whale that was lost. Seeing that the whale was crying, Brook, one of Yorki's crew, suggested that they cheer the whale up with some music. Having cheered the thing up, the whale, Laboon, began following Yorki and the rest of the Rumbar Pirates through their adventures. As Yorki and crew drew nearer to the Grand Line however, Yorki and some of the other Rumbar Pirates asked Brook to convince Laboon to stay in the West Blue since he was the closest to the whale. This was because Yorki and the rest feared that Laboon was too young to face the dangers of the Grand Line. When Brook's attempt to convince Laboon failed, Yorki ordered his crew to ignore Laboon and not play any music in hopes that Laboon would stop following them.
Grand Line
Seemingly having convinced Laboon to stop following, Yorki and his crew sailed into the Grand Line through the Reverse Mountain. Upon arriving at the Grand Line, Yorki and his crew met up with Crocus and asked if they could stay to repair their ship. To their surprise then, they found out that Laboon had followed them into the Grand Line. For the next three months, Yorki and crew stayed to fix their ship whilst singing with Laboon all the while. Seeing that the Grand Line was just too dangerous for a young whale, Yorki asked Crocus to take care of Laboon while they ventured into the Grand Line. As Yorki and crew left Laboon in Crocus's care, they promised to return someday in two to three years and take Laboon back with them.
While in the Grand Line, Yorki and his crew experienced all the hardships that the sea had to offer. Along the way, Yorki and his crew fought against a Marine base. For this attack, Yorki's bounty went up. Despite the challenges they encountered, Yorki and his crew sailed onwards.
Disease
However, after disembarking at a forest, Yorki and some of the other Rumbar Pirates contracted an incurable disease. In order to save the rest of the crew, Yorki decided to take himself and the other infected, and escape the Grand Line through the Calm Belt. With much regret, Yorki told the crew that were still well to give his regards to Laboon. As he lay dying, he asked Brook to play his favorite song to send him off. Yorki's attempt to escape was then written in a report. However the report misinterpreted Yorki's escape as an act of cowardice rather than show his actual reason.
Anime and Manga Differences
In the anime, prior to Yorki being properly shown in the manga, he was depicted as a typical tattoo less pirate wearing a typical tricone. This depiction of him was due to the unclear image of him during Crocus' flashback then in the manga. The image depicted Yorki shaking hands with Crocus however the captain's appearance was obscured along with the rest of the crew, with no indications at the time of the character Brook (who was noted as being thought up at the time of Laboon but not introduced until over three-hundred chapters later). The anime however changed this after he was fully revealed.
Trivia
Yorki's nickname resembles that of the real life pirate, Calico Jack.
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