After owning this film for nearly a year, I finally found the opportunity to watch it without my girlfriend being in the same room with me (She couldn't get past Kazuki Tomokawa's first ballad). Did it help with my viewing enjoyment? That would be a definite yes. Did it help me gain a better understanding of the story?
That's a very good question...
I view Izo as Miike's personal views of what Society has become. Facets of every class, organization and subculture within has grown apathetic, and there seems to be no hope. Izo is the manifestation of a great anger, given birth by a world that he realizes is no longer in need of his services. Upon his death Izo is forever damned to travel the Earth, constantly dragged through space and time and forced to face either those who are out to destroy him or those who, like him, are seeking answers to questions which can rarely be answered. In the rare instance an answer is available, sometimes it's not the one we want to hear. Even if the answer in inevitable, it does not matter. Sometimes there is no rhyme or reason to anything that happens in the world, and Izo is filled with such rage over being betrayed and cast away, that the line between logic and irrationality becomes blurred. In the end everyone's a victim, yet they're all guilty in some shape or form. Izo is forced to face that realization for all eternity, which may make some viewers debate over who the true protagonist of the movie is-Izo or the World (The answer should be obvious, but...).
Most people I've spoken to say they could not "get into" this film. Every one I've spoken to have compared it to Koroshiya 1 or Odishon, which is a mistake. This is not a film about the Yakuza, and it certainly is not a movie that makes Fatal Attraction look like Sixteen Candles. This is a political film; a piece of bloody eye candy with a congealed shell, but political nonetheless. Still, it's definitely worth watching. Make no mistake, this is still "A Takashi Miike Film". All the trademarks that accompany the bulk of his work are present. If you've seen enough of his films (Or at least one), you won't be disappointed. Just don't read too much into it. Try to enjoy it for the great piece of work it is.
10/10