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Any of the now-familiar creepy ghosts in Japanese horror/thriller films. Aka ghost children, women with long black hair, crawly people on a ceiling, and crawly people coming out of television sets.

So named after the various forms of ghost as seen in The Grudge.
I'm too scared to go get your stuff out of the closet alone, because a Grudge Monster might get me!
by Lola Binkerd February 06, 2008
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