Being an assassin from the Hachijo Clan, it was revealed that she was a wielder of the Devil Gene who came to destroy the Mishima clan, causing the downfall and eventual feud between Heihachi and Kazuya. This also led to the origins of the Devil Gene, an ancient curse created by Azazel with it being revealed that he  gave many people the devil gene which included The Hachijos. Her demon alter-ego living in her body, Devil Kazumi, is believed to be the origin of Devil and Devil Jin.