The Japanese are a nation of devoted cinephiles, and it sees, to be horror that excites the country's film fans the most. The apocryphal tale of Cannibal Holocaust out performing E.T. at the Japanese box office likely has some truth in it.
And of course, there is a similar tale of the ridiculous death hag fodder - Faces of Death - out-grossing Star Wars in Japanese cinemas. How fabulous would it be if that is true?
What is verifiable about Japan is that their love of deviant cinema has always made the country a rich breeding ground for creative, pioneering and very powerful horror films. From ghost stories to torture porn, from the kinky pinky to over the top gore fests, Japanese cinema does it all with aplomb.
The horror film community in the West always keeps an eagle eye on what is trending in Japanese cinema. This is due to the simple fact that Japan produces the best horror films in the world and Hollywood just loves to remake them. The Grudge, Ring, and Dark Water are all examples of imitation of Japanese cinema by mainstream American cinema, and as they say in the old adage "Imitation is the highest form of flattery".
But it's also a pale imitation. What you really want is the real experience of sampling Japan's best gutter trash, from the respected classics to the downright reviled and revolting.
If a little Nippon nastiness is what you fancy, you will be well looked after.