Stop Download Kill
From Screamer Wiki
Stop Download Kill is a Korean PSA campaign created by the Busan Metropolitan Police Agency to stop Sexual Predators for voyaing young woman. Details here. Basically this campaign plays out as a Hidden Camera Porn Video capturing a woman's daily life not knowing there's a camera following them. However, When the good stuff begins, A image of a ghost girl appears scaring unexpecting predators. These ads are uploaded to file sharing sites with them being monitor by police. After that, it was basically went viral and was on many news sites around the world.
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NOTE: The following video contains a screamer.