The Happiness of the Katakuris (2001)
There can't be many Japanese comedy horror musicals - I suspect The Happiness of the Katakuris has this particular genre interesection to itself!
The story involves a family who own an unsuccessful guest house. When one of their few guests die they decide to hide the body... which leads to a string of killings, zombies and songs. Truly bizare but definitely a film worth watching.
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