Angel
Angel is a Mary-Sue/self-insert character in several Daria fan works. The creation of author Angelinhel, Angel made her first appearence in "An Angel Named Mary Sue". She is also used as a character in the works "To Understand", "Graduation", "Dear Stacy" and the collaborative work between Angelinhel and The Angst Guy, "Illusions".
Angel is never named as such in the stories and usually simply refered to as "the woman".