Poor kids. Whatever admonishment they might have received about VD in their time- indeterminate heath or sex ed. classes couldn't have prepared them for this. The "It" which trails the unfortunate young people in It Follows might find its eventual victims through the congress of young fluid and flesh, but it's far more nasty and persistent than a case of the clap. Ironically, the only hope - and this is one of many things about It Follows which is less than clear - of ridding oneself of the ghost of hookups past is to have sex with someone else and pass "It" on. Thus, the walk of shame becomes the sprint, the desperate bike ride, the speeding car ride of terror. And yet..."It" does inexorably follow. Pick those partners carefully young lovers. With its placid suburban point of origin and sonic pressure gauge of blaring synthesizers, It Follows pays a good bit of homage to John Carpenter. As with Carpenter's Halloween, only the