Yoruichi Shihōin (四楓院 夜一, Shihōin Yoruichi) is the former Captain of the 2nd Division of the Gotei 13 as well as the former Commander of the Special Forces. Yoruichi, along with Kisuke Urahara helps Ichigo Kurosaki throughout his training to become stronger so that he could face Byakuya.(Wikia)