Kasai has red hair, a common trait among the Uzumaki Clan, golden eyes, and fair skin. He commonly wears his mother's scarf, a tan jacket with sleeves, black pants, and tan sandals. He is average height, has a lean yet muscular build, and tends to have a fierce look of determination in his eyes. During battle, he sports the common Uzushiogakure shinobi uniform and carries several scrolls with him into battle. He has a large scroll on his upper back that is held up with a sash going across his chest and back diagonally. Another very large one wrapped around his lower back, with a sash around his waist attached to the scroll at the back that holds it in place, and he has two small scrolls attached to the outside of each leg, right below his two light tan pouches that carry kunai and shuriken