A member of the Spider Family. Once a young girl who was turned into a demon, she was forced to assume the role of "Mother" by Rui and have her appearance altered. She can control humans using her spider threads, which are attached by small white, red, and blue spiders. She's Always living in fear of Rui.Like most demons, Mother was cruel, unfeeling, and murderous towards humans. She ruthless controlled dozens of Demon Slayers through her threads and manipulated them into killing each other.