Koori Ui

Koori Ui (宇井 郡, Ui Kōri) is a Special Class Investigator and an Investigation Commander in Division I. He is the leader of S1 Squad, and a former protege of Kishou Arima and the partner of Hairu Ihei. He is in charge of the 4th ward.

Appearance
Koori is a short young man of average build, with an androgynous appearance. He wears his black hair in a sleek chin-length bob, and wore a dark-colored suit with a black shirt while on duty.

After the timeskip, he wears a dark-colored vest and light-colored slacks. He occasionally wears a trench coat like other Arima Squad members do.

Personality
Koori has a somewhat easy-going personality, making casual comments or jokes even during tense moments such as the fight with the Owl. However, he also shows an insightful nature when expressing his unease over the outcome of the raid on the 20th Ward.

After the timeskip, he has a strong sense of "Justice" for humans, and seems to be especially cautious towards Haise Sasaki as he is a dangerous ghoul. He is also shown to be extremely prejudiced against ghouls, believing those who claim to be civil nonsensical due to his presumed impossibility for them to be good natured.

Anteiku Raid
Koori took part in the Special Class Investigators' Meeting, in spite of being an Associate Special Class Investigator.

Koori joined the battle against Yoshimura, and remained fighting until only he and Suzuya were left conscious fighting the second Owl that appeared. Koori managed to hold his own for a while before losing his quinque and being forced to use one of Houji's, which he found heavy. The Owl however got the better of him and knocked Koori out of the fight.

When the rest of the squads made their way to the rooftop to fight Eto, Koori threw Houji's quinque to Take Hirako.

Post-20th Ward One-Eyed Owl Battle
After the Anteiku Raid, Koori was shown sitting on a bench with Hirako, discussing about the outcome of the battle and that they were not sure if they really even won the battle.

Auction
Koori was promoted to Special Class during the time skip and had become a member of S3.

He arrived at the Auction after having taken part in the defence of the Quinque Steel Transport and was seen giving orders to CCG members.

Rosewald Investigation
Koori appeared alongside Hairu Ihei and Taishi Fura as a leader of S1 Squad. He held the meeting about Rose Investigations.

Haise Sasaki visited Koori to ask for permission for his plan, but he rejected it for a reason that it does not fit the image of CCG as heroic figures. Afterwards, he was smoking a cigarette with Fura. Koori told him that Haise is a ghoul and is dangerous, as he had seen Haise losing control during the operation with other Arima Squad members. Koori later brought Shiki Kijima to the conference room to reprimand him for uploading a video to the public to provoke Rose ghouls.

After being ordered to take command of the Tsukiyama Family Extermination Operation by Tsuneyoshi Washuu, Koori is approached by Matsuri, who informs him of S2 taking part as support. After thinking ill of each other in their inner dialogues, they part. Koori is then visited by Arima, who has heard of his operation commander position from Marude earlier, and expresses ease as his former superior is the only one he can feel relaxed around after being promoted to Special Class. Koori attempts to tell Arima something, but his former superior is then called on by a fellow employee and leaves before anything else could be said.

Kishou Arima
Arima is Koori's former mentor, having been partnered together in the past. Koori seems to share a rather friendly relationship with Arima, being one of the few that Arima has been shown to smile to. Koori also notes that after being promoted to Special Class, he can't seem to be at ease with anyone other than his former superior.

Take Hirako
As both of them have had Arima as a mentor and partner, they seem to have a friendly relationship with each other and discusses about battles. Ui also apparently rants about various matters frequently when they're together.

Hairu Ihei
Ihei is Koori's current partner. While he is shown to have a strict attitude, his partner remains lax and is at most times taking a relaxed attitude to her superior.

Haise Sasaki
Koori seems to have a professional relationship with Haise. However, similar to a majority of CCG's personnel, Koori still sees Sasaki as a dangerous ghoul which may threaten the CCG. He is against the idea of promoting him, as they will be giving him more freedom to move around, and possibly endanger others.

Power and Abilities
Koori is a highly-skilled Investigator, referred to as the "Hope of the Arima Squad". He is an exceptional fighter, able to survive for an extending time while facing the One-Eyed Owl in battle. An acrobatic daredevil like Suzuya, as implied when stealing Itsuki Marude's motorcycle together with him - though saner. It should be noted that he did not get out until the motorcycle crashed into the ground, yet he was able to survive.
 * Taruhi: A halberd-shaped Koukaku quinque he used in battle against the Owl. It has the built-in gimmick that is able to transform its blade into Bikaku-like whip. It has a ranking of A+.

Trivia

 * His card in the Tokyo Ghoul Trump reveals that he smokes cigarettes. He had not been shown smoking in any of his appearances in the manga until the 38th chapter in Tokyo Ghoul:re.
 * Koori's hobbies include: Making scrapbooks of photos, making collages and horse riding.
 * Koori relaxes by going to karaoke alone, eating yakiniku alone, and drinking with Hirako while complaining.
 * His immediate family is wealthy.
 * In Tokyo Ghoul Trump, he's featured as the "Nine of Diamonds".

Quotes

 * To One-Eyed Owl: "I'm just a coward, you see...!"
 * To Fura: "Sasaki is ... a ghoul."