Koby is a fictional character in One Piece, created by Eiichiro Oda. He is a Marine officer who begins the story as a timid cabin boy forced to work for the Alvida Pirates. After meeting Monkey D. Luffy, he gains the courage to pursue his dream of becoming a Marine. Over time, Koby grows into a capable and determined officer, representing justice, hard work, and personal growth within the series. He often serves as a contrast to pirates and shows the Marine side of the world.