The ’Familiar’ info on the frontsite is a little out of date. Yoshitaka Amano’s concept character designs included Familiars, but they were never a part of the final designs. Pity, really. They seemed like an original, innovative concept… but maybe they were considered too ‘dark’ because of their similarity to voodoo poppets.
However, Eiko’s faithful companion, Mog, is pretty similar to her Familiar….