Ada Cobleigh

Ada Cobleigh was a Templar enforcer working on the streets of London in the nineteenth century. She and her brother, Clyde, were known as the Lambeth Bullies, and the Templars used them to ensure no one caused any trouble.

The two often went on killing sprees throughout Lambeth, until the Assassins Jacob and Evie Frye were directed to assassinate them by Henry Green.

Reference

 * Assassin's Creed: Syndicate