Whilst many have already given credit to the originality of the central plot about a curse being passed on by having sex, let us not forget the works of directors such as David Cronenberg and, if you want to go even more
bizarre, Frank Henenlotter, who have both made
films involving the distortion of sex and the
idea of sex being the conduit
for bad things to happen, And granted, the actual threat in It Follows is a supernatural one rather than one of the body turning on itself, but how many curse movies have there been since Ringu convinced us all that video tapes were credible vessels
for evil beings from other dimensions to cross over and kill us?