I agree with what Turtle Fu says the most about this,s ince some other people have questioned this for some time. Most Japanese, for some reason or another, are not religious zealots and any discernible 'practices' or 'beliefs' related to it have less to do with affiliation than cultural obligation, unlike how we think and view it in the West (its similarly for China and even other Asian nations that have a more significant Christian (Protestant,Catholic,etc.) population and influence like South Korea,the Philippines, or Indonesia.

However, contrary to the statistics there are regarding Japan's secularity since the WW2 dissolution as the Emperor being 'a (sun) god' and the Japanese being 'God's people,' the majority og their population, especially nowadays isn't so much atheistic evolutionists as they are syncretic agnostics (i.e. 3/5 say they believe people evolved from monkeys and there is no 'absolute Truth'), however, that's a misleading notion when the typical ethnic resident there 'meditates @ Buddhist Temples, Gets Married @ christian churches, and has generic prayer times before exams with fellow students and teachers.' In other words, they are deeply spiritual with being overtly specfic to a deity concept like Jesus Christ, Muhammad, or even Buddha at this point. The Confucian values of respect and honoring different beliefs and people in general with the Tao concept of "Universal Flow" in going 'the right path' to their destiny does have religious context to it, even if they don't explicitly speak or adhere to it in public.

Being a Japanese-American and raised in a still Judeo-Christian centered U.S., I'd say she's a spiritual agnostic that leans a little more than most her ethnicity to an absolute deity. She did quote a bible verse in her original "Fly Me To The Moon" cover and mention God in the lyrics to 'Kairo (Sea Route),'This One (Crying Like A Child)' and 'Heart Station' which may have been more for melodramatic and introspective effect. She also was studying/reading a large volume of Catholic history when she was on the TITO tour (she posted a blog pic of it from a library) and did answer in an interview, "Oh, it's you again" when asked,"What would the first thing God would say to you once you got to heaven?"...tongue-in-cheek, I know, but sincere and straightforward nevertheless (unless she was nodding towards reincarnation ); She also said when penning new lyrics to Edith Piaf's "Hymne A L'amour" she wanted the Christian-inspired ending points of 'uniting in Heaven again w/ loved ones' to be from a Buddhist perspective to make it more relative to her Japanese audience, but the final lines can be taken in a fairly universal context. I'd say she's, as well as most Japanese now, are Universalist Secularists, meaning no religious obligations but fairly intuitive to the presence of higher powers and purposes than an earthly existence!