Koby does not act with the reckless bravery that many other Marines exhibit, but rather on moral compunction. Under Garp's instruction, Koby's timidity has been replaced with confidence, although he remains polite, self-effacing, and apologetic if he feels he has done something overly ambitious. He has put his life on the line multiple times for the sake of what he feels is right. Koby has an immense amount of determination and fighting spirit.