Lauren gasped when she rounded the corner into the alley. The object of her revulsion looked up. He was surprised by her sudden appearance. His long hair fell in loose curls past his shoulders. The hair of his bearded chin dripped red with blood. He raised an outstretched hand in front of his face. His other hand let go of the man he had been supporting. The body fell to the pavement. Her attention darted to the apparent victim and Lauren saw that a stream of blood flowed from the man's neck. It traced a path between the cracks in the dirty pavement. Lauren looked back to the... well, the vampire. She knew it sounded crazy, but that's what the guy seemed to be aiming for. Their eyes locked for a few brief moments. His outstretched fingers shook with a nervous energy that she did not mistake for fear.
There are some excellent horror writers who feature supernatural beings, such as werewolves, demons and vampires in their stories. The opening paragraphs describe a vampire doing what vampires do, in full view of the heroine! Chris Dauten's "Lianna's Children" has placed the vampire into an every day situation, using the heroine's reactions to what she's seeing to add visualisation to the reader. Anne Rice also places her vampires in everyday situations, and she gives each character very human emotions - so human that you might want to look at your neighbour a bit more carefully when you close the book! This article is written to give you some ideas for creating realistic characters to populate your horror story.
Good fiction is, by definition, credible - a lie that is easily believed. The most important part of fiction is the characters you create to tell your story. A good horror story character is a fictional being every bit as alive and as much a unique individual as anyone with whom we are acquainted. Your readers should care about him - or her - otherwise they won't care about what the character does or what happens to him - or her - during the story. It doesn't matter whether they like, love, hate or fear him/her. Readers must never fell indifferent towards any character otherwise they will lose interest in the story and not finish it. The uncle who gets drunk and melancholy at a wedding or your high school history teacher who spent most of the lessons reminiscing about growing up in Europe before the second world war; the individual who personified your first encounter with "puppy-love" or the perhaps the one you dated during your college years... every one of these is a real life living, breathing person. And all are absolutely perfect for any horror story.
Your story must be inhabited by characters your readers know and understand. So that means you - their creator - should know those characters well. And there's no reason you shouldn't, because apart from creating them you are also their closest confidant. There is nothing your characters can hide from you. You created them, so you know everything about them, including information they've kept hidden from themselves. In crafting a story about them you've made yourself their closest friend - a psychiatrist of sorts. Your characters must have their own unique and distinct traits, just as you the writer/reader are a unique personality. If believable fiction is based on reality do not fill your story with stereotypical characters. Stereotypes do not to have specific personalities and character traits - their emotions, thoughts and actions are limited by the extremely restrictive mould created by their role. Think of some of the real life stereotypes you know; does your truck driver friend behave like a typical "Truck Driver Dude"? Do all drunks go home and beat up their spouses and kids? Are you - the writer - a typical example of a writer? I doubt it.
Think about what makes you different and unique from other writers and other people. You know how you feel when someone you lies to you, so it stands to reason you'll know what your story character feels or think when he/she experiences the same thing. You understand sadness, happiness, fear, frustration, terror and rage so you can create credible characters that experience sadness, happiness, fear, frustration, terror and rage. You've been embarrassed, you've felt pride, you have felt everything a human being can feel. So your characters will come to life in your reader's mind, animated by your knowledge of yourself, your friends and family and other people. Put them into a credible, believable situation and let them live your story for you!