One evening in October 1943 during a World War II bombing session in London, ARP (Air Raid Precautions) volunteer Howard Leland took shelter in a small derelict house where he stayed for a while until he suddenly felt a presence like he was being watched. He shined his flashlight at the top of the stairs when he suddenly saw a huge tabby-striped cat with sharp claws, horns on it's head, and blazing red eyes crouching down from the top of the staircase he was resting on watching him. Leland stood paralyzed with fear but before he could do anything the cat jumped down the staircase and disappeared before it hit the ground leaving nothing behind but it's spine-chilling yowling cry that seemed to echo on for a while even after it had vanished. The howling stopped when he was rescued by two of his comrades from the ARP. At first he didn't think they'd believe his story because they weren't there but he eventually told them and was surprised to find he wasn't the only one who'd seen the demon cat.
There had apparently been many sightings within the last few years of an immense horned cat with demonic eyes, crouching down and watching people from the top of the stairs in that house. The three men later investigated the house but never found anything. He later went to see renowned clairvoyant John Pendragon, who placed his finger on the house’s precise location on a map, only for his mind to be filled with swirling images of hate-filled cats and an image of a man holding a noose about to hang himself. After describing this vision to Leland, Pendragon asked Leland to try and find more information on the house which is how he discovered that one of the house's former inhabitants had been an ardent practitioner of the black arts, who used to routinely slaughtered large amounts of cats for sacrifice upon an unholy altar. He eventually went insane hanging himself at the top of the staircase. Soon after is when the Horned Demon Cat was first spotted. Pendragon ultimately concluded that the Horned Demon Cat was an elemental, who was conjured into being by the restless spirits of the slain cats, and who may persist there indefinitely.