Mutio, like the rest of her kind - "The Army of Chiron" - is a human-fish hybrid created by the scientist Dr. Zorndyke.
Though all members of her species share the same physical traits, she has red eyes and red spots that physically distinguish her from the others of her kind, making her unique.
She was exiled by the rest of her species for peacefully interacting with Hayami Tetsu - a human opposing Dr. Zorndyke - when they were tasked with carrying out his will, which is to destroy humanity.
