Similar to other aspects of Japanese culture there are elements of their religious beliefs that many would regard as strange and in some cases sacrilegous!
Shinto Translated it means the way of the gods and is the indigenous religion of Japan. The belief is that even within everyday inanimate objects resides a spirit with reasoning and intelligence.
This religion offers little in terms of ethical boundaries and seems to be more a model of the world than a moral guideline.
Buddha Imported from China in the 7th century, Buddhism has integrated itself firmly into the Japanese culture. The underlying premise of this religion is the belief in reincarnation, Karma and striving to reach a state of self-enlightenment (becoming a Buddha).Unlike other religions, in Buddhism there is no all mighty God or gods.
Church While Christianity is a not a major religion in Japan (about 2% of the population), churches are spread out well enough for it to not cause too much trouble for a Christian on the road. It would seem however, that the majority of Japanese Christians take their faith very seriously.

What an outsider may find surprising, or indeed baffling, is that these Shintoism and Buddhism are interchangeable and the majority of Japanese will state that they are both Shintoist and Buddhist. It is often the case that they will marry in a Shinto shrine and have a funeral in a Buddhist cemetary. While this may seem strange to other cultures, one could argue that it is not so different to non-Christians celebrating Christmas (which the Japanese also do).