Millie’s mind was irreparably damaged by her summons; she was one of the first to begin binding demons when the Moribund first happened, back when the horrible side effects were still unknown. Her demons, Myllificent and Diassa, took over and now share her body between them, returning to the side of their master Eligos.
Despite their best efforts, however, they were unable to separate from their human host once her mind was lost, as she became unable to free them from their contracts.
Myllificent - A succubus, mistress of the damned, who confers the ability to charm and quieten men and beasts.
Diassa - A gorgon, whose petrifying stare is a literal death glare.