For me its probably Hokuto No Ken (Fist Of The North Star), Kenshiro taught me how to be a real man (protect the weak, make peoples heads explode). Also more seriously Hajime No Ippo; I forget what chapter this happens but when the kids in Ippo's class who bully asked him if he was doing Boxing to get revenge and Ippo said "No, I don't do Boxing for something as pathetic as revenge. I do it because I enjoy it!" (or something along those lines).
So, what are yours?
So, what are yours?