Basic Info
Hiyori is a member of the Vizard, a rogue group of ex-shinigami. She is seen wearing red sweats. Her hair is styled in a twin ponytail-like feature (somewhat similar to Temari's from Naruto). She seems to be Shinji's superior. She has quite some authority over the other Vizards, but it is unknown that if she is actually the leader. She seems to love beating up Shinji.
She is older than Shinji, despite her appearance. She is a determined fighter and one of the strongest vizards alive. She harnesses her Hollow powers easily, so beating her isn't exactly easy.
Her personality is similar to Orihime Inoue's Tsubaki fairie. She may be small, but she is very bossy. It seems that she tends to yell, and will beat up Shinji on site. She calls Shinji 'Baldie/Baldy' (despite that he is not bald). It seems that she is stronger than Shinji.
If she is stronger than Shinji, then she can beat a lieutenant with ease, and she is somewhere around the captain rank. It also seems that she has almost-perfect mastery of her hollow abilities, despite being the slowest one to beat her hollow form (at 69 minutes, 2 seconds).
Synopsis
She first makes her appearance in Chapter 189, when she approaches Shinji about Kurosaki Ichigo. She beats him up for not taking him in, despite that Shinji explains Ichigo doesn't want to be a Vizard. She then tells Shinji to take Ichigo by force.
She is then found with the other Vizards at the HQ when Ichigo seeks 'advice'. She tells him that if he's strong enough, he'll join the Vizard, but if he isn't, then he can take a hike. Ichigo pisses her off by saying that he doesn't want anything to do with the Vizards, he just wants to learn to suppress his inner hollow.
Hiyori then fights Ichigo after stopping Ichigo & Shinji's brawl. Hiyori then lets Ichigo witness her Hollow powers, saying that Ichigo's recruitment isn't his choice at all, the descision is up to the Vizards and the Vizards alone.
During the brawl, she continously screams for Ichigo to either let his hollow out, or to use his bankai. Ichigo won't do either, so she decides to kill him. She is stopped, however, by a released Hollow Ichigo. The other Vizards manage to stop Ichigo from doing any further harm to Hiyori. When Shinji asks for any compliments, all Hiyori does is quiver in awe and fear.
When the Vizards train Ichigo, she decides for Ichigo to face Ichigo in Ichigo's inner world. During the Vizards' brawl with Hollow Ichigo in the real world, she tells Shinji that he isn't facing Hollow Ichigo, making it so that the Vizards each have 10 minutes, and with 6 Vizards fighting, that's 60 minutes to face Hollow Ichigo (keep in mind that Shinji isn't fighting, and Hachigen is holding up the barrier).
Powers & Abilities
Hiyori seems to possess the full powers of the Vizard, able to awaken her inner hollow and the ability to use a zanpakutou. If she is stronger than Shinji, it would appear that she would know the Cero hollow ability. Plus, Vizards start out as shinigami, so she should be able to perform a variation of 'shunpo'.
Hollow Form
Hiyori first calls upon her Hollow form. While in the process Ichigo is stunned by her amazing ability, but all Vizards can display this ability. When in full-hollow form, her strength increases, allowing her to attack with speed & power.
Zanpakutou
She also carries a zanpakutou. She carries it slung over her back, much like in a manner similar to Hitsugaya Toushirou. She draws it with her fight with Ichigo at the HQ, but doesn't release a shikai or anything. It seems that she relies more on her Hollow form.
Trivia
- She said that she is a less gentle person than Shinji.
- If she was the leader of the group, then she would be expected to be older & wiser than most of the Vizard, with the possible exceptions of Hachigen, Love, & Rose. She could be wiser than Love, but possibly not older.