Ellen Danielle Dunkel is one of the main characters of El Goonish Shive. She was created by the Dewitchery Diamond that split Elliot from his gender-swap curse. She's usually a good character, but in her first appearance, the Sister arc, she was trying to be a villain by framing Elliot of her actions, but failed spectaculary and ended up destroying Omega Goo Monster. It was later revealed that she was influenced by Magus.
When trying to get Elliot to problems, she called out his science teacher from being uncaring towards his students, threatened a bully named Tony, which is something that Elliot has wanted to do for a long time, and told principal Verrückt that he looks like Hitler. Verrückt's response was just wondering why nobody had told him earlier, changing his wig and finally understanding why little kids are afraid of him.