She was the warlike and brutal Captain-General of the Hosts of Alsion, and for three days she fought against "the revered ruler" of Alsion. She was cast out of the world of light and into the world of shades in defeat.
She arrived on Earth in 1860 through a portal located on Gralstead House, which was considered a family curse. She had tried to come through once before and was considered a ghost by individuals like Clementine Scrivener, as it was vague and undefined, not properly existing in the world until it's physical form was completed. The Doctor managed to track it as it left a trail of dark matter particulates. It was immense physical pain during the journey from it's section of space to Earth. She smelt like old fish, or old potatoes according to Cedric Scrivener.
She was considered a beauty in her home planet. She found the air of Earth choking.
She was described by Cedric Scrivener as an 'elephant woman', her body twisted and malformed. According to Sir Edward Scrivener the looseness of the skin was mottled, and the weight of the enlarged skull twisting the curve of her spine, either caused by a genetic mutation or a bungled attempted at trying to emulate a human according to the Doctor. Leela stated that she had two faces, one behind the other, the first being crumpled with too much skin, her body hunched with pain, "like something that should have died long ago but went on getting older and older", and her second face "being like a darkness inside, a tall fierce pointed cone of darkness, a faceless face". She needed to eat living human brains to survive.
Eventually sensing the return of the completed Corona of Alsion to Britain, where she had been living in Gralstead House of six months along with Edward Scrivener, she transformed into her true form, pointed and cone-like full of darkness, as Leela had described it.
After engaging in battle with a revived Palito, she defeated him, and followed the Corona as it flew upwards into the portal back to her home world. But the Doctor had loosened numerous links on the Corona, making it functionally useless to her when she got back home. (AUDIO: The Ghosts of Gralstead)