"Black Leg" Sanji is a pirate and the cook of the Straw Hat Pirates, the former sous chef of Baratie, and the third son of the Vinsmoke Family. He is officially the fifth member of the crew and the fourth to join, doing so at the end of the Baratie Arc. Since he was born in North Blue, he is the first Straw Hat not to originate from East Blue. He is one of the Monster Trio in the crew alongside Luffy and Zoro. His dream is to find the rumored All Blue, which is where East Blue, West Blue, North Blue, and South Blue meet along with their wildlife, a chef's paradise. He has a bounty of Beli177,000,000, which is only valid if captured alive. Sanji is a slim, yet muscular, long-legged young man with blond hair and keeps his hair brushed over one side of his face. For the initial part of the series, this was the left side. Due to his left eye never being seen, many fans questioned whether he had one at all. In the manga it was usually covered one way or another, but is seen in the anime (episodes 20, 21, 27, 82, 128, and Movie 6 and 10 although usually very briefly and most likely due to animation errors).
Later, after the two year timeskip, he switched his hairstyle so that it covers the right side. It also appears that Sanji's hair is less straight and scruffier after the timeskip. Among Sanji's physical traits are his distinctive eyebrows. Both form a spiral but at different ends. His right eyebrow forms a spiral at the outer end, while his left eyebrow forms a spiral at the inner end. This means his face is asymmetrical with the position of his eyebrow spirals. This, however, is not fully seen due to his hairstyle. He still gets very upset if somebody, typically Zoro, mocks him over the spirals. Though, on rare occasions, Sanji's other eye was seen in the anime, the spiral was never witnessed. While Sanji's eyes usually seem black, he was depicted with grey-blue eyes in the anime at the beginning of Thriller Bark Arc. Sanji almost always wears a black, double-breasted suit with a tie and a long-sleeved, buttoned shirt of varying colors, usually orange, blue, turquoise, or black, with or without pinstripes. His outfit changes on a more frequent basis than most of the crew. Sanji is one of the crew's top three fighters (despite not having one of the top three bounties, which Robin and then Usopp takes). While Luffy usually fights the primary, and strongest, antagonist, Zoro and Sanji usually fight the second or third strongest enemies, depending on the story arc. Although Sanji and Zoro would usually let their rivalry impede their fighting performances, they have proven to be a near-unstoppable force if they agree to cooperate for the battle, as seen when they instantly turned the tables against the Groggy Monsters. Though he's one of the physical powerhouses of the crew, Sanji can also be a skilled tactician if need be. This was particularly evident in the Alabasta Saga, where he was responsible for both disguising himself as Mr. 3 and fooling Crocodile into believing that the Straw Hats were dead on Little Garden, and posing as "Mr. Prince" to get the Straw Hats out of Rain Dinners in Alabasta. In the Skypiea Arc, when he and Usopp snuck onboard the Maxim in order to save Nami, Sanji took a detour and destroyed the ship's main engine, which would have crippled the flying vessel, had it not been for the back up engines. During the Water 7 Arc, he went on his own and waited patiently at the train station in case Robin were to leave. With his instincts confirmed of her departure, Sanji left Nami a Baby Den Den Mushi and a letter of his intentions...though half the letter was babble of his love for her, and even worse, the hiding place of the letter was very obvious marked with red paint, with large hearts for Nami and a threat for anyone else not to read it.
During the Enies Lobby Arc, he took over the fight with Jabra and reminded Usopp, that he is better suited for assisting Robin from a distance, while he himself was better suited for front line fighting. And he later shut the Gates of Justice, giving the crew an opportunity to escape the Buster Call. In the Dressrosa Arc, he was the first one who noticed Law's true objective in establishing the Pirate Alliance, noting that he was focusing too much on Doflamingo. Sanji also had a fondness for reading books when he was younger and knows of many legends, albeit they are mostly "Fairy-Tale" like in nature opposed to Robin's "Historic" recollection of legends. In fact, he had already heard of the legendary ingredient the Blue-Finned Elephant Tuna before he even saw it. And he has also been familiar with the tale of Montblanc Noland through the book King of Liars, Noland. And through a book on Devil Fruits he learned of the Suke Suke no Mi, although since he only had interest in that particular fruit what else he knows on Devil Fruits is currently unclear. Although Sanji is primarily known for his incredible leg strength, the rest of his body is shown to be just as superhumanly strong and durable, including his arms, which enables him to use an array of handstands, for his fighting style, which makes him much more versatile in certain combat situations. In an SBS, Oda stated that Sanji's kicking power is 21 Bats (the power to break 21 wooden bats in one kick). One example of his inhuman strength is shown during the Skypiea Arc, while riding on the Going Merry, he was capable of lifting a large mallet that looked to have weighed several tons (though this is unlikely, as it belonged to Usopp and as such was probably another Usopp Pound decoy) before using it to slam an Impact Dial that was sitting on top of a barrel; needless to say, the impact would have most likely busted a hole on the Going Merry's deck had it not been absorbed by the Dial. Another example of his physical might is seen when he was able to hold Absalom in place by gripping onto his leg, despite the latter's reinforced muscular structure and being struck multiple times while doing so. His upper body is also superhumanly durable as well, having been known to take head-on attacks like Kuroobi's fists and half of Jabra's "Gekko Jushigan" just before counter-attacking them with his kicks, and, along with Zoro, he has also shown himself to be resilient enough to be able to take Bartholomew Kuma's "Ursus Shock" attack head-on, despite having just endured an exhausting battle with the giant zombie Oars, and still remain conscious afterwards, before being knocked out by Zoro. After his two years of training, his body has become much more stronger and faster, being able to break the neck of a Pacifista with only a kick, critically damaging it, and not showing any trouble afterwards (something he was not able to do before the timeskip) or being able to break a Seastone cage just with kicks (as seen in Episode of Luffy). He is also now able to withstand pressures of over 5000 feet under water without a coating, a depth which would have crushed a submarine. His overall endurance has also increased, as he was seen being able to take direct punches from both Jinbe and Luffy to the head, from both sides simultaneously, with relatively minor injuries (though left bleeding on the ground).