Kūkaku Shiba

is an ill-tempered fireworks expert and the somewhat authoritative older sister of Ganju. She lives with her family in ridiculously-themed houses (which she changes in design and location regularly) on the outskirts of Soul Society. She is missing her right arm, which in the anime is replaced with a prosthetic, to which the reason of the loss of her right arm remains unknown. Kūkaku is the head of the Shiba family, which fell from the status of nobility after her brother, Kaien, died. Because they knew only that Kaien was killed by a Shinigami, both Kūkaku and Ganju are distrustful of Shinigami when first introduced. After Kaien's killer, Rukia Kuchiki, explains how he died and apologizes, the Shiba make amends. Kūkaku seems to have some kind of relationship with the Urahara Shop, knowing Yoruichi Shihōin and claiming to have worked with Kisuke Urahara in the past. She can perform high level Kidō spells, and she carries a short-bladed sword on her back but it is unknown if this is her Zanpakutō or not. She helps Ichigo Kurosaki and the gang into Soul Society to rescue Rukia during their first visit, launching them from her cannon with a Kidō spell.

Synopsis
After an unsuccesful attempt to break into Seireitei after their arrival in Soul Society, Yoruichi leads Ichigo and his friends to Kūkaku, knowing that she has the means to get them into Seireitei, and asks for her help. The group is astounded by both Kūkaku's house, and her overall character. She leaves no doubt that she is the master in the house, strictly (if not brutally) disciplining Ganju and Ichigo when the two, after they realize that they already met in Rukongai, want to continue their fight which began there.

Kūkaku gives them a spiritual orb and tells to practice. She witnesses ichigo almost demolish her house with that orb. She launches Ichigo, Ganju, Inoue, Ishida, and Yoruichi from her fireworks cannon the next day. She wishes them luck. She is next seen talking to the gate guard Jurinbo. She tells him to get ready to go into Seireitei. she was last seen restraining Aizen, Gin, and Tolsan.

Power and abilities
Vast Spiritual Power

Enhanced Strength

Kidō Master: Kūkaku is a master of her family's earth and fire spells and does not use normal shinigami kido.