Shintaro Kago doesn’t really do interviews outside of Japan. The illustrator’s work has garnered a cult following around the world, celebrated for its distinct mix of horror, sci-fi and psychedelic erotica. But when the 49-year-old agrees to take a call at home in Tokyo, the idea of talking about himself or his art causes clear discomfort. Little is known about his life and he speaks in halted sentences: one-line answers that convey an air of secrecy.