Sapi

Sapi was the fish salesman who sold Sanji the Blue-Finned Elephant Tuna. He is half fishman and half human. He has a small ponytail that resembles a fish fin.

In the anime, he met with Sanji, but did not sell him the fish. Instead, he told him about the competition with the Blue-Finned Elephant as the prize.

Trivia

 * He is currently the only known person to be a cross species of a fishman and a human.