At 30 years old, Aizawa stands tall and muscular but slender with a distinctly pale complexion. His signature feature is his messy, shoulder-length black hair that hangs messily in front of his face. He is rarely seen without dark, heavy-lidded eyes and a perpetual layer of unkempt stubble. Because his Quirk, Erasure, requires him to maintain direct eye contact with his targets, his natural eyes are often flat, tired, and deeply bloodshot from overuse. In his everyday civilian clothes or when teaching, or in his hero suit, he wears a worn-out, baggy black outfit that mirrors his laid-back and fatigue-driven personality. This ensemble consists of a long-sleeved shirt and matching dark trousers tucked into his heavy boots. He is often depicted carrying a heavy yellow utility belt and is almost never seen without his trademark gray, tattered "binding cloth" wrapped securely around his neck. So unbothered is he by conventional fashion—that his favorite place to sleep is in a custom yellow sleeping bag on the floor of his classroom.