A member of Tower Tom's gang, Dreg was a part of the attack on Red Tourette's gang at the federal ration stockpile. Although the attack was a failure, Dreg and Hook managed to capture two hostages for them to leverage for food. One of whom was Lily, she was captured after a blow to the head rendered her unconscious.
Dreg was completely ignorant of whom Dreg was dragging to his boss' – Tower Tom – room, whom was pleasantly surprised he realized who they captured. Immediately recognizing her importance as a hostage, he sent word of her capture.
Dreg is mentioned only in Fallout 4.