Koby does not act with the reckless bravery that many characters in the series exhibit, but rather on moral compunction. He has put his life on the line at least twice for the sake of what he feels is right. 

Koby has grown thinner and taller, standing close to Luffy in height. He has also gained a cross-shaped scar above his right eye, presumably earned under Garp's heavy-handed tutelage. His hair has grown longer and shaggier since his growth spurt, but it has retained its kobi pink color.