A mesmerizing 8k ultra-realistic depiction of a menacing demon, inspired by the Night King from Game of Thrones and the dark imagination of George R. R. Martin, showcasing a full body view. The demon is adorned in intricately designed purple and blue neon armor, with an ornate and otherworldly aesthetic. The scene is illuminated with dramatic, cinematic lighting that highlights every hyper-realistic and meticulously crafted detail. The image captures a high level of focus and depth, trending on art platforms like ArtStation, rendered in stunning 4k using Unreal Engine 5 for an immersive visual experience. The demon's piercing gaze and ominous presence create a chilling atmosphere in an aspect ratio of 9:16.