Bio: Galatea was a professional actor and also a witch. In the early part of the 20th Century, she fell in love with a popular and handsome actor named Farley Fairfax. When he scorned her love for another, she summoned a demon to mess up his face durig a performance, whcih the audience interpreted as part of the show. She later drowned.
Etrigan the Demon was able to summon her through the temporary usage of the body of Glenda Mark, who resembles her former physical appearance. She restored Fairfax's face, but he died of shock when it aged. She also possessed a wax döppelgänger of herself that was destroyed in a fire.
It is not known if she needs something in her likeness to achieve physical form, or if it is simply easier for her to do so.