ロッテンガールグロテスクロマンス (Rotten Girl, Grotesque Romance)

Background
The song was originally uploaded onto Nico Nico Douga on July 21, 2009. It currently has more than 465,000 views on the site, making it one of Machigeriita-P's most popular works. The song tells a story of a stalker(Miku) who is stalking someone who is dating another woman. The song itself is said to be based off of a mysterious murder case in Tokyo, Japan which was never revealed to the public. Although, however, a report was given to a member of the public. The report had details of the murder case and victims of it, one of the victims being a man who had a love for cats and was sent three parcels filled with dismembered cats(In many translations of the song, there is a part where Miku sends a box with a dead cat head in a box to the victim). The story may or may not be true.