Thousands of years ago, the Sleepwalkers who are Earth-born human-like beings, were once worshipped by humans as gods in ancient Egypt. They possess such supernatural abilities including the one: "dimming", able to turn and any other object or person in their own presence into invisible. They also feast on the life energy of young virgin girls in order maintain their youth and their strength. But somehow, all that changed and these creatures were renounced and even shunned as monsters and demons, probably due to their weakness to cats. They intensely feared and hated cats, even the Sleepwalkers were born with the same animal organs. Whatever the case, the Sleepwalkers couldn't have the adoration nor love, respect from the human race, and thus they became outcasts.