Yukio has teal eyes, dark brown hair, and wears glasses for nearsightedness. He has two moles under his left eye and another one under his mouth. He is sometimes worried about his moles. Beginning in the Kyoto Impure King arc, Yukio's eyes sometimes shift to look the same as Rin and Satan's. Following the events of the Of One Cloth arc, the iris of Yukio's left eye is a bright bluish white. Because of the attention he gets from girls at school, he is considered to be fairly attractive.