Eiichiro Oda, creator of One Piece, has revealed a rather touching fact about Monkey D Luffy and the Straw Hat Pirates.
A Reddit thread has translated a question from volume 96 of the One Piece manga, where a fan asked Oda why Luffy does not give nicknames to the members of his crew. "Luffy is the kind of guy who doesn't want to remember any names, because he doesn't care, so he makes up a name based on the respective person's look," Oda explained. "But when someone joins his crew, he makes sure to remember their name properly."
Over the course of his adventures, Luffy has befriended and recruited many members to his crew, including master swordsman Zoro, sniper Usopp, navigator Nami, and womanizing chef Sanji. The absence of nicknames for these characters helps showcase the bonds that have formed between Luffy and his crew.
Created by Eiichiro Oda, One Piece focuses on Luffy's quest to find the ultimate treasure, known only as "One Piece," so that he may reign as the King of the Pirates. The manga first debuted in 1997, and has spawned an entire multimedia franchise including several theatrical films and video games.