Stacy
http://www.imdb.com/title/tt0368296/
Teenage girls start going into a state of euphoria and produce a drug like substance called, "Butterfly Twinkle Powder" out of their pores. They then turn into zombies that can only be killed by being chopped up into 213 pieces. The world slids into a deep depression as all there girls disappear, and population plummets. While a team of near zombie female cosplayers dick around in an infected military base, they find out that the zombies are eating people because they just want to be loved, and think that eating people will get at the love inside of people. Meanwhile a lonely man strikes up a relationship with a giddy, near zombie schoolgirl, and starts telling her stories with his hand puppets. When the girl finally turns full on zombie, he figures out how to not get eaten, has sex with her, the resulting half zombie offspring becomes the next stage of human evolution, and all the worlds religions get replaced by a religion based on the aformentioned hand puppet show.
Really. That's the plot. For seriously.