Savagery...

Klaus snapped his fingers, reducing the remains of Aya Middlestone to ash. She had caused enough damage, and now it was Klaus's turn to correct some of those mistakes. 

From the memories he had extracted from Aya, he could tell she had wreaked significant havoc.

Klaus saw how she became an assassin and who had recruited her. She had been in college studying to become a surgical doctor when the apocalypse descended.

She awakened a darkness-related talent and an Assassin Class, just like her daughters. However, she never had the privilege of moving through the shadows as they did.

Nevertheless, after a certain woman discovered her talent, she approached and recruited Aya to join the Dark Order, where she adopted the code name Lady Death.