Parodied: Bob is actually moonlighting as a stunt double, as practice to become a real actor (it turns out he can quote Shakespeare while dodging pianos).
Zig Zagged: Bob seems at first to do this all the time. But actually, it depends on his mood. If he's in a crummy one, just touching him wrong will knock him out cold. The rules are inconsistent about this though.
Koichi gets into all sorts of Amusing Injuries while chasing after Arsene III. Arsene got freaked out by Koichi's sheer determination and...handed himself in just to preserve his own sanity. Koichi got promoted to the head of ICPO, with subordinates under him who are insanely loyal and devoted to their jobs.
Played For Laughs: Bob is continuously subjected to a series of Amusing Injuries, all without taking harm or complaining.