Jamieson Ridenhour remembers himself as a 10-year-old, reading the original “Dracula” novel and staying awake with his mother well past midnight to watch classic horror movies. Nearly four decades later, Ridenhour has built a career from his early obsession. “Good horror writing works when it’s more than just the horror, when it has some kind of psychological depth to it,” he said. “There’s a metaphor for something else going on.”