Isamu is a 6'8" tall, 200 year old demon in the Demon Slayer universe. Isamu consumes humans without remorse. Isamu has long, black hair and a single horn sticking out of the left side of his forehead. He wears a heavy scarf around his neck, and a large purple kimono. Isamu has no lips, only very sharp teeth. Isamu has a long pointed tongue, and he speaks very formally. Isamus' skin is a deep gray color. Isamu has a long, skinny tail with a tuft of hair at the end. Isamu has four arms.