Vinsmoke Yonji

"Winch Green" Vinsmoke Yonji is the fourth son and youngest child of the Vinsmoke Family, making him both a prince of the Germa Kingdom and a commander in its military arm, Germa 66. As noted by the Straw Hats, Yonji heavily resembles his brother Sanji. He has almost identical facial features, including the curly eyebrows common to the Vinsmoke siblings. However, his hair is green and slicked back into a cowlick, his eyebrows curl in the inverse direction (both face the left side of his face), and he lacks facial hair. He is also more muscular than his brothers, who all have comparatively thin builds, and notably taller than the rest. When commanding the forces of Germa 66, Yonji wears a green suit and orange ascot, with his shirt bearing the number "66" in gold, and a black hooded cloak bearing a green "4" on the left.

He wears a striped belt with the Germa 66 symbol as a belt buckle, metal gloves, sunglasses, and black earphones on the top of his head. When outside of his combat attire, Yonji wears a light-colored short sleeved shirt with a frilled collar, along with a striped belt and plain black pants. For formal functions, he also wears a dark floor-length, single-shoulder royal cape with an upturned collar and a neck clasp. As a child, Yonji's hair was styled with a small cowlick on top of his head. He also wore a light shirt with the number "4" on it. As Nami observed, Yonji, like his older brother Sanji, exhibits lecherous qualities. He is immediately struck by Nami's beauty, and is seen ogling Nami's bounty poster when Germa 66 depart from their brief meeting with the Straw Hats. After witnessing Nami slapping Sanji, he exclaims that he is into her fiery personality. He has been described as callous and stingy, refusing to help a dying Luffy and challenging the Straw Hats to plunder the Germa 66 ship for the cure for Luffy's condition. His elder sister, Reiju, claimed that he was rotten to the core. 

Yonji seems to take amusement in instigating or observing conflict, as he offered to lead Sanji to Niji for a fight with a smile and acted similarly when he tried to goad the Straw Hats into attacking him. He is also proud, getting angry at Reiju when she humiliated him in front of the Straw Hats. This proud nature was in evidence again when, upon suffering defeat at Sanji's hands, Yonji was infuriated and swore to make the latter pay for his actions. According to Reiju, he lacks the ability to feel empathy and sympathy. Since birth, Yonji is incapable of sympathy and empathy due to the genetic modifications done by his father. As a child, Yonji took part in bullying Sanji, joining his two eldest brothers in mercilessly beating and mocking Sanji's compassion in preparing food for others. This shows that he neither tolerates nor values any such trait, which he believed was worthless to royals. In the present day, Sanji himself claims that, despite his hopes to the contrary, all of the members of his family have only gotten worse with time. Yonji is also very mindful of his family's affairs, deciding to not get involved with the Straw Hats in order to ensure that Sanji's wedding would not be jeopardized. He also tried to reprimand Sanji after hearing that Sanji was refusing to cooperate with their family's plans for an alliance with Big Mom. When discussing the mission on Broc Coli Island, Yonji expressed interest in making money as he suggested that they could have taken both sides and doubled the profit.