An almost final question based on a conversation we had recently: what do you believe is the defining element (or elements) of a successful horror novel?
Horror must evoke the emotion of fear or dread in the reader to be successful. The fear is typically caused by placing an ordinary character in an extraordinary situation. For example, in my novel Till We Become Monsters, fear is elicited by seeing one of the characters—just an ordinary person—become so consumed by his resentment of his brother that jealousy possesses him, evolving that character into something grotesque and deadly. There should also be a level of plausibility that grounds the story, which allows the reader to connect to the plot and characters before the chaos and hell break loose. The sibling rivalry between the two brothers during their childhood in Till We Become Monsters is a conflict that is believable. Some readers may even be able to relate to the relationship. However, that rivalry is taken to the extreme to where it becomes the trigger point for the horror in the plot. These elements are kind of my holy trinity for horror writing: evocation of fear, the ordinary suffering from the extraordinary, and incorporating plausibility.