Dreamscape isn't on that site with her fics anymore.
It can be found here though.
http://www.nocturnal-light.net/fanfiction/story/313/DreamscapeSummary: While her nights are occupied fighting evil, her dreams are haunted by a devastatingly sexy, not to mention thoroughly evil vampire. The sort of vampire that embodies the definition of forbidden fruit; the sort of vampire Buffy can only have in fantasy. But how thin is the line between dreams and reality? More importantly: how thin does she want it to be? Complete