Japan's is a culture built on bullying, from the very beginning. Specially through the enforcing of the senpai-kouhai relations.
To read more about the subject, see this:
http://legacy.lclark.edu/~krauss/advwrf99/causeeffect/akikocause.htmlYou can also see typical japanese bullying in action in shows like GTO or Black Lagoon (the first episode, at least), several manga, even comedy ones like Yankee-kun to Megane-chan, or you can go all the way and watch Hideaki Anno's favourite movie, which is pretty much a thesis on bullying in Japan: All About Lily Chou-Chou.
In this thread, we discuss the subject of bullying in manga, anime, and japanese media in general.