Hairu Ihei

Hairu Ihei (伊丙 入, Ihei Hairu) is a First Class Ghoul investigator and the partner of Koori Ui. She is the deputy leader of S1 Squad

She is a veteran of the Owl Suppression Operation and serves as a member of Squad 0, commanded by Kishou Arima.

Appearance
Ihei is an attractive young woman, with straight light pink hair cropped into an angled bob. She has very delicate features and a sleepy expression, with heavy-lidded eyes. She seems to favor men's wear styles with a vest and slacks as opposed to the skirts worn by most female Investigators.

When serving as a member of Squad 0, she wears a trenchcoat with a hood pulled up to conceal her identity.

Personality
Ihei comes across as a normal young woman, though already a veteran Investigator. She eagerly and politely greets the Quinx, and is happy to finally meet people her own age. Though their superior, she wants to be treated as their peer and seems a bit uncomfortable with how young she is compared to everyone else she works with. She seems to have quite a tomboyish personality.

She is noted by Haise as to being relentless during battle, leaving brutal scenes behind her.

Owl Suppression Operation
She took part as a member of Squad Zero, fighting on the front lines and at Route V14.

Auction
While still unidentified, Ihei is one of the hooded members of Squad Zero that arrives to help secure the Auction Hall. Along with her team, she surrounds Hinami Fueguchi and aids in her capture.

Rosewald Investigation
Ihei appears at the S1 meeting alongside her partner, Koori Ui. After the meeting, she approaches the Quinx Squad and introduces herself to them. She notes they are all the same age -- meanwhile, Shirazu blushes and gets teased for his awkwardness around her.

She later took part in the ambush of Matsumae and her followers along with Taishi Fura, Shiki Kijima and Nimura Furuta. She dominantly fought against Matsumae with outstanding performance and she eventually wounded her belly. However, Matsumae had a chance to escape from her when Kijima captured Yuuma the Rose ghoul. She was disappointed that Kijima obtained ownership of the Rose ghoul in spite of her great action.

She is later put in charge of the vanguard troops for the Tsukiyama Family Extermination Operation's second location, the Lunar Eclipse building. She easily fights her way in along with Kijima and the other CCG investigators and is confronted by Matsumae, Mairo, and several other Tsukiyama family ghouls near the top floor. Upon witnessing Matsumae's kagune-formed sword and shield, Ihei expresses interest in getting it as her quinque. Despite fighting more or less on even grounds, she ends up slipping on a pool of blood, creating an opening for Matsumae to pierce Ihei with her kagune.

Koori Ui
Ui is Ihei's current superior partner. She calls him Koori Senpai (郡先輩, Kōri Senpai). Ihei stated that she wants to work harder than Sasaki and Ui so that she may earn Arima's praise.

Kishou Arima
Ihei admires Arima greatly and she stated that she wants to work harder than Sasaki and Ui so that she may earn Arima's praise despite knowing full well that he doesn't praise anyone.

Haise Sasaki
Ihei stated that she wants to work harder than Sasaki and Ui so that she may earn Arima's praise, although Sasaki's rank was below Ihei's before he was promoted and she calls him by his first name without an honorific.

Ginshi Shirazu
Ihei hopes to get along with Shirazu since he is her age.

Kuki Urie
Ihei hopes to get along with Urie since he is her age.

Tooru Mutsuki
Ihei hopes to get along with Tooru since he is her age.

Saiko Yonebayashi
Ihei hopes to get along with Saiko since she is her age.

Powers and Abilities
Like Arima, she began working as a teenager and has served in the elite Squad Zero, suggesting she possesses abilities far beyond the norm. While working with her squad, she's seen wielding a long bladed Quinque of unknown type.

She is a swift acrobatic fighter with incredible dynamic vision and reaction time, capable of evading attacks even at point-blank.

Quinque

 * Aus: A rinkaku quinque that was able to cut through Matsumae's kagune easily, although her kagune wall was previously strong enough to even withstand Urie's power.

Trivia

 * Prior to her formal introduction, Ihei cameos in Chapter 141, Chapter 142, and Re: Chapter 31 as one of the six cloaked members of Squad Zero.
 * Ihei spoke to Matsumae "速いしょや (I'm quick, aren't I?)". This is in Hokkaido dialect, so she is apparently from Hokkaido.
 * Ihei's hobbies include: Combat practice, drawing, having conversations with herself, and observing Arima.
 * Ihei wants Arima's IXA.