Yoruichi ShihÅin is a dark-skinned woman with golden-colored eyes and long purple hair, which she keeps up in a ponytail. Her standard attire consists of a backless, black sleeveless undershirt, an orange over-shirt with two white straps on each shoulder, a large beige sash around her waist, black stretch pants and long beige wrist warmers, secured by bands, and long beige leg warmers with brown light shoes, allowing for stealth and easy use of Shunpo. She previously wore a beige neck warmer, which she pulled up to cover her face in order to hide her identity, but seems to have forgone its use. She, unlike any known Shinigami, is able to transform into a black cat for long periods of time. In this form, she has a distinctive male voice and golden eyes. 110 years ago when she was a captain, she wore the same sleeveless and backless OnmitsukidÅ uniform, with long black wrist guards that Suì-FÄ“ng wears now, but had a black ribbon tied around her neck. She also wore a long-sleeved captain's haori. Her hair was also much shorter and cut in a style similar to Suì-FÄ“ng's current hair-style but without the braids. At some point prior to this she wore the white OnmitsukidÅ uniform of the correction corps.
Yoruichi is intelligent and witty, holding an intimate knowledge of the Soul Society and its workings, as she was the former leader of the OnmitsukidÅ and the Second Division's captain. Although of noble birth, she acts differently from most other nobles, very much like Kaien Shiba. For instance, she instructed Suì-FÄ“ng to refer to her without using honorific suffixes, but reluctantly settled for being called "Yoruichi-sama" ("Lady Yoruichi" in the dub). She also transforms into her human form directly in front of Ichigo on several occasions just to see his reaction to seeing her naked, which she even teases him about. Another note of her eccentricity is that she speaks in a dialect that elders use, such as identifying herself as "washi" (a term that usually old men define themselves with) instead of more feminine terms like "watashi" in both her human and animal forms (though specifically for the Japanese version).
Although relatively calm and mature when a situation calls for it, Yoruichi is quite laid-back and playful, often teasing or flirting with those younger than her, such as Ichigo Kurosaki at the underground hot spring, a younger and hot-headed Byakuya Kuchiki, Suì-FÄ“ng before her time as a captain and Kisuke Urahara, childhood friend, former underling and fellow ex-captain. Yoruichi prefers to drink milk, which fits with her practice of transforming into a cat.