Ancile is the soul of nightmares, who had followed the scent of darkness all the way to Japan.
Ancile, known as the soul of nightmares, possesses the power of lurking into the soul of humans to see their true fears. They use the intell they got to fight their enemies. Ancile is neither human nor do they have any animal-like appearance. They consinder themselves as "them" and "their" since they don't want to be set on the same level as humans.
Ancile — In ancient Rome, the ancilia were twelve sacred shields kept in the Temple of Mars. According to legend, one divine shield fell from heaven during the reign of Numa Pompilius, the second king of Rome.