Sanemi is a tall man of very muscular build, with spiky long white hair and large almond-shaped eyes with purple irises. His face and body are covered with scars, accrued over his many years of fighting demons. He is usually seen wearing a crazed expression on his face. He wears a green-tinted version of the standard Demon Slayer uniform, unbuttoned to expose his chest and abs with a white long sleeved shirt over it with the kanji for kill (殺さつ, satsu?) etched on the back.