Usopp / "Sogeking"

Usopp (ウソップ) is a pirate and the sniper of the Straw Hat Pirates. When Usopp was first introduced, he was often (comically) labeled as the "Liar" of the Straw Hat Pirates. Usopp is a tanned, skinny teenager with black curly hair and a long nose, which is apparently an allusion to Pinocchio, a wooden boy from a story of the same name who possessed a nose that would stretch after he lied. He usually wears a dark yellow plaid bandanna, special sniper goggles, brown overalls with a white sash and no shirt. Usopp inherited his famous nose from his mother, while the rest of his face closely resembles his father's.
Oda claims that Usopp is most represented by the armadillo. Oda has also said that he uses the color yellow to represent Usopp, and he smells of gunpowder.
Sogeking is Usopp's alter-ego developed during the Water 7 and Enies Lobby arc. When he left the crew, later seeing the others trying to save Robin made him feel guilty for leaving. He stated to Sanji and Franky that he cannot help them fight for this reason. He hastily 'disguised' himself in a mask and cape and began calling himself "Sogeking, the king of the snipers". During this facade he sometimes dons a deeper voice which can be seen as the "true" Sogeking. Everyone except for Luffy and Chopper already knew that Sogeking was Usopp at the sight of Usopp's significantly long nose.
As his alter-ego Sogeking, Usopp was able to fight alongside the others without having to deal with his departure. During his time spent acting as Sogeking, Usopp began to realize that while he was one of the weaker crew members, his role as the crew's sniper and a supporting crew member make him more valuable than he thought. Ultimately, he has been recorded as Sogeking on his bounty.
During his fight with Perona, Usopp showed signs of a split personality and even went so far as to argue inside his head with his alter ego over their situation. Although they are technically the same person, Sogeking in comparison to Usopp is much more confident and took over once Usopp adorned the mask again, only slipping back into Usopp once the mask came off. Whether or not Usopp is developing Dissociative Personality Disorder (formerly Multiple Personality Disorder), is debatable and has yet to be confirmed by the author or within the story.