This animated version of Ichi The Killer is the prequel to Takashi Miike's splatter-filled comedy-gore film.
Showing Ichi's childhood (teen years), leading up to just before the live-action film of the same name, this film takes everything that's wholesome and moral, chews it up, and spits it out.
Takashi Miike even does a cameo as the voice of Kakihara (the naked guy running at the start), which is a nice shout out to his fans.
Not as good as the live-action counterpart, but if you liked Ichi The Killer, then you will enjoy this nice little back story.