The Irregulars from Tower of God. Normally, people who climb the Tower to get their deepest desire fulfilled have to be Chosen and are invited as Regulars. Not these guys. They came and kicked the metaphysical doors open by themselves and every time that happened, the Tower underwent drastic changes. Five Irregulars are known. One was a man-made god who defeated the entireruling structure of the Tower and then simply disappeared. Before him came a person who slew a Physical God and could create life. The third followed the former into the Tower, climbed it ten times faster than anyone elsenote it took him 50 years and built a N.G.O. Superpower that rivals the government. The fourth one was almost completely immune to magic and could copy any spell on sight. And the last one was an incredibly normal girl who stabbed her best friend in the back. People are not very fond of Irregulars. They are afraid of them.
In Our Little Adventure, Angelo invoked this feeling when he confronted Randi and Peganone during their quest to capture Umbria. He probably would have for Eva as well, but she retained her resolve due to her Paladin's fear immunity. What happened to Eva due to her not backing down and running away was accordinglyhorrifying.
In The Mansion of E, Uncle Frederick's bed-mate is called variously the Woman of Mystery or the Scary Lady.