Boogiepop

Boogiepop is a light novel series by Kouhei Kadono. Volume 1, Boogiepop and Others was written in 1998 and is still ongoing.

Synopsis
There is an urban legend that children tell one another about a shinigami that can release people from the pain they may be suffering. This "Angel of Death" has a name—Boogiepop. And the legends are true. Boogiepop is real.

Boogiepop wa Warawanai (2019)
is a Japanese anime television series produced by Madhouse Studios for the Winter 2019 season. It premiered on AT-X on January 4, 2019.

Synopsis
There is an urban legend that tells of a shinigami that can release people from the pain they are suffering. This "Angel of Death" has a name—Boogiepop. And the legends are true. Boogiepop is real. When a rash of disappearances involving female students breaks out at Shinyo Academy, the police and faculty assume they just have a bunch of runaways on their hands. Yet some students know better. Something mysterious and foul is afoot. Is it Boogiepop or something even more sinister...?

Boogiepop Phantom (Anime)
is a Japanese anime television series produced by Madhouse Studios. It aired for 12 episodes between January to March 2000.

Synopsis
Five years ago, a string of grisly murders shook the city to its core and now the rumors have begun once more. Boogiepop... Everyone knows that during the night, once meeting her and you never come back. People tell each other the stories and laugh: no one believes that she can possibly exist in this day and age. Still, strange things appear to be going on and the darkness is taking on many forms. Something is out there. Are you safe?

Official

 * Seven Seas Entertainment: Boogiepop

Other Sources

 * Light novel:
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