It is only in the anime that Shiba Kukaku's missing right arm is replaced with a prosthetic piece. She has some kind of relationship with the Urahara Shop, knowing Shihoin Yoruichi and claiming to have worked with Urahara Kisuke in the past. Kukaku is able to perform high level kido spells and carries a kodachi tied around the remaining portion of her right arm.
Beautiful cosplayer from the “Japan Expo Sud”, a French convention in Marseille! And it looks like Kukaku is quite the shutterbug herself. Thanks to Clad for the cool photography and for sending this!