Justin was abusive, but though he seems to have adopted the teaching philosophy of "pain is an excellent motivator," he was more emotionally abusive and manipulative than physical. He encouraged a distance between them and other children, and was gradually training the two of them to use violent magic without realizing that it was wrong, so that they be his personal enforcers.
As a former Warden, he participated in the chase after the necromancer Heinrich Kemmler. During or after this, he found and took the skull-bound air spirit owned by Kemmler at the time, but kept its discovery and retrieval a secret from the White Council, who thought it had been destroyed. Some time after this, DuMorne left the Wardens.
DuMorne adopted and apprenticed ten-year-old orphaned wizards Harry Dresden and Elaine Mallory, shortly after they came into their powers. He began to teach them the basic principles of magic.(reference needed)
One day, Justin turned Elaine into a thrall. He attempted the same thing on Harry, but Harry escaped. Justin sent He Who Walks Behind after him. Harry came back to save Elaine. He performed a fire spell, burning the house down, killing Justin.
He Who Walks BehindEdit
- Main article: He Who Walks Behind
Harry had always assumed that Justin had sent He Who Walks Behind after Harry to kill him. Now Harry considers the possiblity that He Who Walks Behind hadn't really tried to kill him, that instead, he manipulated Harry into killing Justin. And, that He Who Walks Behind was quite possibly Justin's mentor as opposed to Justin being the one who simply summoned and sent He after Harry.
In the seriesEdit
- Main article: Dead Beat
- Main article: Ghost Story
In Ghost Story, Harry recalls how Justin taught him his first fire spell: "Flickum bicus!", Justin gave him a Wilson baseball mitt. Later, Harry recalls the day he came home early from school worried about Elaine and sensed black magic in the air. Elaine Mallory was sitting still, quiet, Justin DuMorne stood at the kitchen doorway. There was a straightjacket on the table next to Harry's copy of The Hobbit. Justin ordered Harry to sit, and when he didn't, Justin sent a blast of kinetomancy at Harry who used the force to propel him through the window for an escape.