Sagot :
Answer:
Joy Boy was an extremely relevant figure of the Void Century who played an important role in the history of Fish-Man Island and left behind a certain item of unimaginable value in the last island of the Grand Line. He was first mentioned on the Ryugu Poneglyph read by Nico Robin while at the Sea Forest.
Answer:
Joy Boy was an explorer that lived during the era of the 100 Year Void. It isn't verified if he was the first pirate or the ruler of the Great Kingdom, but he is mentioned at various points in the manga.
Explanation:
Luffy being Joyboy was confirmed in fishmen island in chapters 626 647, & 649. Luffy having the power to control Shirahoshi, the ancient power poseidon.