Fray

Fray is a comic book series taking place in the Buffyverse and officially considered canon by Joss Whedon (who wrote it). The comic was done in an 8 issue miniseries introducing the character.

The premise for the series is that sometime in the 21st century there is a huge battle in which most are killed and all demons are banished from this world. So after for centuries there still remains a slayer line, but none are called due to now demons. However by the time of Fray things have changed. There are now vampires running around, "Lurks", as they are called in Fray's time.