You wouldnt probably classify this as a horror but more so of a romantic dark side vampire movie.....but i like "Let the Right One IN" the original. Its about a girl vampire who is actually too young to keep killing her prey. (vampires dont age right)....so she has to get a boyfriend to do it for her. But as her original boyfriend killer starts to age and get old and starts fuckin up on tha kills.....she needs a new younger boy. And she chooses a boy that gets bullied a lot because it seems to be a good reason to kill. Love this movie.