Sapi

Sapi was the fish salesman who sold Sanji the Blue-Finned Elephant Tuna which he claimed to have caught himself. In the anime version, his name was given as Ness.

Appearance
He is half fishman and half human. He has a small ponytail that resembles a fish fin.

History
In the manga, he met Sanji and just sold him the fish. While in the anime, he told him about a competition that has the Blue-Finned Elephant Tuna as a prize.

Trivia

 * He is currently the only known person to be a cross species of a fishman and a human.
 * In the anime version, though he was given the name Ness, the One Piece Blue: Grand Data File has stated that his actual name is Sapi.