Hatchan  

Hachi, はっちゃん

Hatchan (はっちゃん) is an octopus fish-man known as "Hachi" (ハチ) by most characters. Despite being not very bright, he's a skilled swordsman using rokutōryū ("six sword style"). He fought with Zoro during the Arlong arc and was defeated by him despite Zoro suffering from a fever and severe blood loss. Hatchan is extremely helpful and friendly outside of battle but can also be cruel to humans like other crew members. He addressed Zoro politely when they first met and gave him a ride on his back. In later manga, he went on many adventures, meeting a mermaid and opening a floating takoyaki restaurant. It's revealed that Hatchan, along with Chu and Kuroobi, planned to open a takoyaki store when they were younger. His nickname "Hachi" means eight in Japanese, referencing his octopus fish-man nature. However, Hatchan claims his name is Hatchan and "Hachi" is just a nickname. The suffix "-chan" in his name signifies "cute" or "little" in the Japanese language but Oda explains it comes from the last name "Chan," common in Chinese.