Fiction Express: The Vampire Quest

James is an ordinary boy, but his best friend Vince is a bit, well, odd. For one think, it turns out that Vince is a vampire. His parents are vampires, too. And so are the people who live at No. 38. There are vampires all over the place, it seems, but there's nothing to worry about. They like humans, and they'd never, ever do anything horrible to them.
Unless, that is, the world runs out of Feed-N-Gulp, the magical vegetarian vampire brew. Which is exactly what's just happened...