Jillian was a mutant member of the Neyaphem, who served as a soldier under Azazel with several of her half-siblings. She accompanied the Neyaphem when Azazel teleported to La Isla des Demonas, Azazel's island on Earth. When there, she came into conflict with the X-Men who were looking for Nightcrawler. In the conflict, Jillian attacked Archangel, whom she hated for his angelic appearance. Nightcrawler and Husk fought her off. She appear to have a crush on Nightcrawler as she told him she find him attractive and asked him if she interest him.
Jillian was created by Chuck Austen and Philip Tan and made her first appearance in Uncanny X-Men # 429 in 2003.
Jillian has large, bat-like wings allowing her to engage in self-propelled flight; heightened aerial agility and reflexes make her highly adept at flying and areal combat.