Yoruichi Shihōin (四楓院 夜一 Shihōin Yoruichi?) is an old friend of Urahara Shop owner Kisuke Urahara, and so uses it as a place of residence when she is not abroad. She is a slim, sexy, dark-skinned woman with deep-violet hair. She can also transform into a black cat and back at will (much to Ichigo Kurosaki’s displeasure as she would tease him whenever she appeared naked before him after transforming). Her cat form gives her a deep voice, which leads many characters to initially believe she is a male and thus call her “Mr. Yoruichi”.
Yoruichi Shihōin is very easy-going and she insists that Suì-Fēng avoid formalities when speaking to her. She tends to avoid combat and will not engage her enemies unless her allies will lose without her intervention. When first introduced, she helps Ichigo and his friends infiltrate Soul Society. As the series progress, it is revealed that Yoruichi is a former captain of the 2nd Division, head of the noble Shihōin clan, and was the Commander in Chief of the Secret Mobile Corps. Therefore, she is highly knowledgeable in Soul Society’s history due to her background as a leader of one of the four highest ranking noble families.
According to a citation from Kisuke Urahara when he explained to Hiyori Sarugaki, any squad captain in the Gotei 13 who has had the Secret Mobile Corps under his or her control (usually 2nd Squad) will be a formidable military force in Soul Society. As Yoruichi was the leader of the Secret Mobile Corps and also a squad captain herself during the pendulum period and also a leader of a high ranking noble house, it has made her position in the Soul Society as one of the most intimidating and respected. A century before the start of the series she abandoned all of her military and noble house positions by helping Urahara, Tessai Tsukabishi, and the Vizards escape to the human world. Series creator Tite Kubo identifies Yoruichi as one of his two favorite female characters in the series (along with Rangiku Matsumoto), citing that he “has a lot of fun drawing her and creating stories with her.”
Yoruichi Shihōin has lived up to her former position as a captain and Commander in Chief of the Secret Mobile Corps due to her prowess throughout the series including when she immobilized Espada Yammy Riyalgo bare-handed. While she is very skilled in all Soul Reaper tactical combat, Yoruichi Shihōin has always been presented in the series as extremely powerful in hand-to-hand combat and the use of flash steps (瞬歩 shunpo?), a high-speed movement ability. While the ability is common for any competent Soul Reaper, her speed movement is almost unmatched, leading her to be called the Goddess of Flash (瞬神 shunshin?, English Anime: “Flash Master”). Even after a century later, Byakuya Kuchiki is still unable to surpass her speed.
Yoruichi Shihōin is also highly skilled in “Flash Cry” (瞬閧 shunkō?), which is an advanced technique that combines hand-to-hand combat and kidō abilities. The use of shunko allows the user to fight bare-handed against any opponent’s weapons without being injured. She has never been seen wielding a zanpakutō in the current or gaiden storyline, though is shown carrying a kodachi-like blade during flashbacks. She has also been shown using gauntlets and sabatons during her latest fight against Aizen, though these have been destroyed since then. Despite the fact that she is no longer the Captain of the Second Division, she does retain and use the uniform she wore at the time, which is unique for its absence of any clothing over the back or shoulders. It is explain that this is due to Yoruichi’s mastery of Shunkō, which when utilized, destroys the fabric on the back and shoulders of the one using the technique. To date, only Yoruichi and Suì-Fēng have been shown to actively wear this particular uniform.
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