She's Austere Howl, and the daughter of Mary Campbell.
Gleaming Eye and Austere Howl have all sorts of history - Gleaming Eye once wiped out nearly all of Austere Howl as a precaution that they might be infernal demon worshipers. Gemma, as the daughter of the Queen of Austere Howl was often separated from her mother and raised under the watchful presence of Gleaming Eye.
Ever been to Scotland? Want to have been? Or perhaps Gemma's been to wherever Asya and Miguel were trained?