Joy Boy is a title that seems to be of great relevance in the world of One Piece. The first time it was mentioned was on Fish Man Island, and it referred to a person who lived at the time of the Lost Century.
Mentions of the name
The poneglyph on Fish Man Island was different from the ones shown so far. It was more reminiscent of a letter of apology and was signed with the name “Joy Boy”. Moreover, King Neptune mentioned the name when thinking of a promise regarding Noah.
It is later learned that the first known Joy Boy was a man who is said to have lived about 800 years ago.
The Joy Boy from the Lost Century still managed to enter the last island of the Grand Line. There he left a treasure, which was found about 800 years later by Roger’s band of pirates. The pirates had to start laughing at the sight of the treasure, and Gol D. Roger expressed that there was a history of laughs associated with the treasure and the island, and that he would have liked to have lived in Joy Boy’s lifetime. Kozuki Oden returned to Wano Country after his trip with Roger’s pirate gang, planning to open the borders of the sealed-off country before Joy Boy showed up there one day.
Kaidou also has knowledge of Joy Boy. When Luffy fell into the sea during their fight, Kaidou said that Luffy could not be Joy Boy, even though it seemed so at first.
- The name Joy Boy may have come from the Javanese king Jayabaya (note: needs link), who was also called Joyoboyo.