|Previous Affiliation||Gotei 13, Soul Society|
|Previous Position||Lieutenant of the 12th Division, Head of the Shinigami Research and Development Institute|
|Previous Division||12th Division|
|Previous Partner||Kirio Hikifune, Kisuke Urahara|
|Base of Operations||Vizard Warehouse|
Hiyori is a very short, brown eyed, blonde-haired girl who wears her short hair in spiky pigtails with her bangs clipped together by three clips. She wears a white shirt and a red jogging suit, the latter with white lines running down from the shoulders and decorated with the first kanji of her name, as well as yellow flip flops.
Hiyori carries her Zanpakuto over her back. On each cheek, under each of her eyes, she has three freckles. She has an overly long fang protruding from the upper left side of her mouth. This physical characteristic has caused some people to call her "snaggletooth". She appears more haggard and not as sharp as she did during her days in Soul Society, with tired lines under her eyes.
Despite her small size, Hiyori is an aggressive and short-tempered girl with rather violent tendencies, her most common victim being Shinji Hirako, whom she frequently abuses, usually by smacking him with one of her sandals or kicking and punching him in the face. She has made it a reflex to use him as a human shield when necessary, and shows him an obvious lack of respect, a gesture which he seems to return. This behavior dates back to her time as a lieutenant, despite Shinji outranking her back then. She has highly aggressive tendencies, often make her lash out at other people even under normal circumstances.
She shows very little respect to the majority of people around her, easily losing her temper and getting into fights. Hiyori seems to harbor a hatred of both Shinigami and humans. As a result of her thorny disposition and possible insecurities, Hiyori never displays much emotion besides anger, and always appears to be frowning.
Hiyori was one the Lieutenant of the 12th Division, under Kirio Hikifune, whom she viewed as a mother figure. Her feud with Shinji existed at the time as well, as she would often attack him, despite his status as a captain. When Hikifune left the division to become a member of the Royal Guard, Hiyori was shattered. Kisuke Urahara became the new captain, but despite his attempts to bond with her, she remained vicious and hostile towards him.
Some time later, Hiyori, along with eight other Shinigami, was experimented on by Sosuke Aizen and became a Vizard, for which they were condemned to execution by the Central 46. Luckily, they escaped with Urahara's help, and the group, now in exile, set up base at Karakura Town.