Irimi is a woman with long, dark hair with long, parted locks in the front. Irimi dresses fairly casually. At first glance, she seems to be a rather solemn and taciturn woman. After the timeskip she has her hair shorter due to cutting it.
In the past, Irimi's hair was considerably shorter.
Her ghoul mask resembles a Doberman's face.
She normally keeps to herself and is quiet and reserved. In subtle moments, she can be quite annoyed and speak out her honest thoughts however. She has also been shown to be especially kind towards Touka Kirishima, and Hinami Fueguchi. Like Enji Koma, she has been with Yoshimura long before they were employees at Anteiku and is quite loyal to the manager. When she was about to die, she was willing to accept and embrace her death, described by Renji Yomo, it was punishment for her past sins.
In the past, Irimi was a very murderous ghoul who possessed a more savage and cruel disposition, with some of her actions including the brutal killing of the entire squad of Ghoul Investigators sent to kill Irimi and her gang, the Black Dobers. She then proceeded to sadistically leave a single survivor after brutally scarring him.
A decade prior to the series, Irimi was the leader of a notorious ghoul gang of the 20th ward recognizable for wearing black Doberman-like masks. A rival of the Apes and their leader, the Devil Ape, the two gangs clashed often. She was involved in killing many associates of Chuu Hachikawa. She may have been the ghoul who disfigured Hachikawa's face during this time as well. After meeting Yoshimura, she drifted from her violent past and became a waitress at the café, Anteiku. After joining Anteiku she was immediately put to work as a barista, to the disbelief and incredulity of Koma who had spent months only cleaning before Yoshimura let him brew coffee (and was relegated back to cleaning when Irimi took over the counter). She became popular with the male customers, and also became friends with a female customer named Tsubasa. It was also revealed that she had an unnamed boyfriend around this time. During a conversation with Tsubasa, the other woman expressed admiration for Koma and how hard he worked. This led to Irimi feeling jealous on how easily Koma was able to interact with humans, and she vowed to work harder at this. A few years after she began working at Anteiku, Eto Yoshimura stood outside of the café and witnessed her and Koma having an argument about which made better coffee. After the shop was closed later that evening, she bid the manager goodnight. Also, around this time Irimi and Yoshimura are seen observing Renji Yomo and his comrades as they are about to battle Kishou Arima in the 4th ward. For some reason, they are focusing on Yomo specifically and when Irimi asks Yoshimura how they should proceed, the latter states he doesn't know. Years later, Touka asked Irimi what the meaning of "Anteiku" was. Irimi smiled and stated she should ask Yoshimura herself sometime, noting that the meaning itself was beautiful.
After Ryouko Fueguchi is killed by Kureo Mado, Irimi is shown looking on sadly as Yoshimura reveals what happened to Touka. She appears distressed when Touka suggests they kill the investigators. When Yoshimura tells her and Koma that he will supply them with descriptions of the investigators responsible for Ryouko's death she nods in assent.
After Shuu Tsukiyama's predations were announced on the television in Anteiku, Irimi agrees with Touka when she notes he has become much more active since Rize Kamishiro's supposed death. She notices when Tsukiyama enters the café, and observes him with a smile.
After members of Aogiri Tree attack Anteiku and kidnap Ken Kaneki, Irimi is present with the other staff members in the cafe's meeting room when Yoshimura states they should consider that they'll never see him again. Upon hearing this Nishiki insults the manager, which Irimi admonishes him for. After it's decided that they will attempt to rescue Kaneki, Irimi smiles when Yoshimura reveals she'll be coming with them. After Koma expresses disappointment that he won't be coming with them, Irimi states he is better suited to staying at the café. While the rest of the group infiltrates the 11th Ward Base, she remains outside with Hinami and Yoshimura. She uses her enhanced hearing to monitor the movements of the CCG and Aogiri members battling inside the complex. She then relays this information to Yomo via a wireless transmitter. When Hinami compliments her abilities, Irimi then notes that Hinami should be able to do so as well as Ghouls have enhanced senses. She explains how her hearing ability works, and in the process notices the presence of Ayato Kirishima. However, she has difficulty in gathering information from the annex of the building as it is soundproofed, and asks Hinami for assistance.
Due to the powerful vibrations caused by Kaneki's battle with Yamori, Hinami is able to make out that he may be there, and Irimi compliments her for this. Irimi then once again monitors the movements throughout the complex, and then notes the investigators are heading towards the other Anteiku members inside. She is then tasked by Yoshimura with keeping Hinami safe while he creates a diversion to buy time for the rest of the group. After the conclusion of the battle, Irimi observes the rest of their team from afar with Hinami and Yoshimura. When she asks if they should let them know that they are there, Yoshimura states it's unnecessary. She then expresses concern over Yoshimura's injured state.
After the conclusion of the battle, Irimi tends to Yoshimura while he recuperates from his injuries. When Hinami questions about Yoshimura's injured state, Kaya assures her that he is fine and will be back to full health in no time. Later, when Koma is talking with Nishiki and Hinami, Irimi comes and retrieves him for an unknown task.
Raid of Kanou's Lab
After Koma states Touka is studying for her entrance exams, Irimi notes that she has seen her many times at the library. When Nishiki asks if Irimi could help them in the café, she declines as it is her day off, and then apologizes for this. She then notes that Touka is working so hard that she seems like a different person. When Roma Hoito shows her amazement at how Kaneki eliminated the Ghoul Restaurant, Irimi silently ignores her and drinks her coffee.
Post-Raid of Kanou's Lab
Irimi is seen alone stoically drinking a cup of coffee. While preparing for the CCG's attack on Anteiku, Irimi disposes of all the cafe's files. After she sadly drinks a cup of coffee prepared by Yoshimura, she agrees with Koma when he states they are with him to the end.
Owl Suppression Operation
When the CCG arrives at Anteiku, she exits the café and greets them as the Black Dog. She then eliminates several investigators before revealing the presence of her former gang, the Black Dobers, who once occupied the 20th ward. She orders her subordinates to die for her, and they then begin their assault.
She then continues to slaughter investigators before she notices a particular sound. Subsequently, several of her comrades are shot off the rooftop, but she evades any attacks. She admonishes one of her subordinates for being slow, and is then greeted by her old enemy, Chuu Hachikawa. Away from the battlefield, Nishiki states Irimi is too nice as she and the others don't realize that their sacrifice leaves a bad taste in his mouth. She battles Hachikawa and his squad members, and mocks him when he tries to hit her. After he insults her, she insults him in turn and tries to land a critical blow on him. However, she is stopped by Take Hirako who wounds her shoulder, and she notes that he's stronger than he appears. Irimi continued to battle Hirako while avoiding Hachikawa's attacks. After she reached a balcony an elderly civilian woman stepped out to see what was going on, and Kaya was surprised by her presence. Hachikawa attempted to kill both Irimi and the civilian, and fired his quinque at them. Irimi decided to shield the old woman from Hachikawa's attack and promised to curse her until the day she died.
When the two of them land on the ground below, Kaya shrugs off the elderly woman's questions and laments how soft she has become. She is forced to release her kagune earlier than she expected to. Using it to enhance her senses even further, she attacks the investigators while using her senses to evade their blows. During the fight she reflects on her past actions and if she could die. She is then defeated due to the injuries she sustained previously. As Hachikawa looms over to deliver a killing blow, Irimi states she will see him in hell. However, Kaneki suddenly appears and attacks Hachikawa, thereby saving her. She then comments on what a bad kid he is. She then informs Kaneki of the seriousness of their situation, and when he decides to fight regardless she tells him the strengths of the investigators they are fighting. While Kaneki is fighting she notes how strong he has become and how much he must have suffered. She applauds him after he wins the battle. She then gathers the remainder of her followers. After Kaneki tells her to hide while goes to help the manager, she that complains he's ruined the plan, and is confused as to why he seems so happy. She then goes on to states that Yoshimura is facing Special Class Investigators, and that they will escape through Route V14 where they will all meet there later. During this time, she is seen holding hands with one of her subordinates. Once she and Koma reach V14, they are intercepted by Kishou Arima and Squad 0. Their remaining subordinates choose to fight them in order to give their leaders time to escape. They exit V14 and aren't pursued as Kaneki holds off Arima.
During the Tsukiyama Family Extermination Operation, Shuu Tsukiyama learns from Matsumae that Mirumo Tsukiyama and the family servants chose to remain behind so that they would have a greater chance of escaping. Upon hearing this, he remembers Irimi and the other Anteiku members who stayed behind to fight the CCG a few years previously, and laments how history is repeating itself. 
Rushima Landing Operation
During the Rushima Landing Operation, Irimi takes part in the battle between Shuu Tsukiyama, the White Suits, Miza Kusakari and the Ui Squad. Kuramoto and Irimi believed they recognized one another, and she teases that he's seeing a ghost. Irimi briefly fought Kuramoto, and dodged Takeomi Kuroiwa's sudden attack, causing them to exchange blows before she switched opponents with Tsukiyama. While the others fought, she and Koori Ui engaged in a high speed battle. Koori stabbed the face of a ghoul meaning to flank him before the two exchanged words when Taishi Fura attacked her from behind. Koori used the opportunity to get in an attack on her, but she is protected by a hooded individual who blocks the attack by grabbing Taruhi's blade bare-handed. After the conclusion of the battle, Irimi is shown walking alongside Tsukiyama and the ghouls they rescued towards the beach to wait for Mirumo Tsukiyama, who is coming with three large ships to transport them back to the mainland. 
Post-Third Cochlea Raid
Irimi joyfully reunites with Kaneki at :re, and knees Koma from behind when he starts to say something she was thinking of. She then explains herself and apologizes. After recounting how they were able to escape from V14 due to Kaneki efforts, she states his actions were not in vain, but apologizes for the pain they caused him. However, after Kaneki states having everyone together makes it feel like Anteiku all over again, she grimaces. She then tells the others to stay safe as they head to a meeting with other ghoul groups at Tsukiyama's location.
CCG Lab Infiltration
After Kaneki decides to infiltrate the CCG's laboratory in order to obtain rc suppressants for Akira Mado, he assigns Irimi to support the White Suits in their attempt to divert the CCG's attention. After Kaneki instructs Koma to remain at :re, Irimi realizes (to her annoyance) that was what he wanted to do in the first place.. During the mission, Irimi arrives on the battlefield to assist the other members of Goat against members of the Clowns. She initially acts as a sensor and notifies Nishiki of the ten enemies on his left. After the arrival of V, she tells Kaneki that he must continue on to the lab and leave things to them. She goes on to state that the Goat members present are more capable than he thinks, and that if they can't survive the current battle they won't be able to succeed in the long run. When she advises Kaneki that if he wishes to lead others he must learn to rely on them, he thanks her. After the battle's conclusion, she notes that everything has been settled.
Post-CCG Lab Infiltration
After Kaneki decides to dissolve Goat's bases and remain on the move in response to the emergence of Oggai, Irimi is shown helping to move essential items out of :re. When Koma complains that moving seems to be a part of their lifestyle, she tells him to just get on with it. She then tells Touka and Kaneki that they will see them later.
Goat Wipeout Operation
When Goat mobilizes a provisions squad to obtain food for half a year, Irimi is assigned to lead a communications squad consisting of herself, Koma, and some others. Her role was to connect the provisions squad to those on standby, and so she waited with her squad on the outskirts of the 23rd ward. After the CCG attacks Goat's base in the 24th Ward, the decapitated bodies of her communications squad members are shown, and she and Koma are nowhere to be found.
It is revealed both she and Koma had died at some unspecified point, and their bodies were taken by Kaiko to Akihiro Kanou. Using Quinque technology known as "Spieldose", he was able to revive her, Koma, and their former gangs (the Black Dobers and the Apes) and place them under V's control. After arriving on the battlefield, they were shown to have retained their original personalities, but spoke in a broken pattern in which they repeated certain words over and over again. She attacked Koori Ui and overwhelmed him. However, before she can land a finishing blow her attack is blocked by Mougan Tanakamaru, whose shoulders are injured by her and Koma. After the conclusion of the battle against V, Irimi is show lying motionless on the ground with Nishiki crying over her.
Like Enji, she possessed a deep loyalty to her employer as he helped her fix herself inwardly.
In the past, they were rivals with opposing gangs that clashed frequently. However, the previous hostility left along with their joining at Anteiku. She and Enji were often together, sometimes having quarrels about small things, but never in a hostile way, such as whose coffee was better or who was the stronger ghoul. However, despite not referring to each other in the most respectful terms, such as Irimi thinking of Koma as "that monkey", they can be nonetheless be considered friendly to each other. She was used to the majority of his hearty jokes, such as translating his joke calmly to Yoshimura before the battle of Anteiku. During the Owl Suppression Operation, they both wondered whether the other was dead, almost in a sarcastic fashion.
She acted as an elder sister figure to Touka. Irimi and Touka were comfortable enough with each other for Irimi to share personal memories and details of her past life. In turn, Touka was relaxed with her, displaying her rough attitude and speaking her mind which Irimi neither minded nor reprimanded her for.
Like Touka, Irimi acted similar to an elder sister figure to Hinami. She always spoke to Hinami with kind words and passed on some of what she knew to her, such as the teaching her how to focus and discern the details of sounds based on their ghoul ability.
Despite not interacting with him much she is grateful to him for rescuing her during the Anteiku Raid and greets him joyfully when they reunite after their respective battles. When Goat is founded she defers to Kaneki's leadership without opposition.
Irimi was one of their co-workers and fellow waiters in Anteiku, where Irimi, along with Koma, taught the two of them how to brew coffee and becoming close with them during their years working in the cafe under Yoshimura. Eventually, upon her death and resurrection as a human Quinque and her permanent death in the hand of her former comrades, Nishiki and Yomo were both shown to mourn for her. Nishiki himself seemed to have been brought to tears.
Powers and Abilities
Ghoul Physiology: Irimi possesses an ukaku kagune, as well as higher physical capabilities along with heightened senses apart from her ukaku kagune. During battle, Irimi uses a dog like fighting style where she primarily uses her extremely sharp nails to inflict several deep cuts on her opponents and uses her extreme agility in tandem with her four limbs to make nimble dodges and attacks.
- Ukaku Kagune: Her kagune takes the form of two beetle-like wings with a tail between them.
- Superhuman Senses: She has excellent hearing abilities, able to differentiate the volume, type, deflection and rhythm of sound waves to comprehend details of enemies and the surroundings. Using this method, she can pinpoint ghouls and their location through vibrations emanating from their kagune. Irimi can also take advantage of this ability to predict the movements and attacks of enemies during a fight before they are executed to dodge and use in her favor..
- Superhuman Agility: Irimi can swiftly dodge a barrage of attacks from multiple enemies at once within milliseconds, allowing her to fight several high ranked ghoul investigators easily.
- In Tokyo Ghoul Trump, she is featured as the "Ten of Spades" alongside Enji Koma.
- Irimi is removed from the anime of Tokyo Ghoul:re outside of appearing in flashbacks, likely to limit the number of characters so as to suit the show's episode count and focus.
- In :re chapter 99, after Kaneki reunites with Koma and Irimi he says having everyone together again makes it feel like "Anteiku." Frowning upon hearing this, the numbers 2 and 3 appear visible in her hair. These reference the tarot cards The High Priestess (II) and The Empress (III). Additionally, a J is shown in her hair which refers to a white pillar in the High Priestess' imagery called "Jachin" (meaning "the beginning").
- Irimi is heavily associated with The Hierophant (V) tarot card. On the cover of chapter 131  the fabric of her dress wrinkles around her left hip to form the number 5. In :re 178  while laying motionless on the ground blood trickles from the right side of her mouth. When looking at this sideways, it's apparent that the blood forms the number 5 as well.
- To herself: "Have I made the right choices until now? I don't care about that. "Right" or "wrong", they don't matter. In the first place, there might not have been anything like that. But the things I've chosen until now, the sins I've committed, entering Anteiku with that ape man, passing my time during those days so boring that they make you yawn, and being able to die for someone: I think those are all "fine". Yeah, today I can die."
- About Kaneki: "Damn it, each and everything, such a bad kid."
- To Kaneki: "If you choose to stand atop others, You should learn to rely on them."
- Tokyo Ghoul Chapter 130
- Tokyo Ghoul Chapter 125
- Tokyo Ghoul: Past Chapter 6
- Tokyo Ghoul:re Chapter 62
- Tokyo Ghoul Chapter 112
- Tokyo Ghoul Chapter 143
- Tokyo Ghoul Chapter 16
- Tokyo Ghoul Chapter 32
- Tokyo Ghoul Chapter 58
- Tokyo Ghoul Chapter 59
- Tokyo Ghoul Chapter 66
- Tokyo Ghoul Chapter 67
- Tokyo Ghoul Chapter 79
- Tokyo Ghoul: Void Chapter 5
- Tokyo Ghoul Chapter 84
- Tokyo Ghoul Chapter 121
- Tokyo Ghoul Chapter 126
- Tokyo Ghoul Chapter 127
- Tokyo Ghoul Chapter 128
- Tokyo Ghoul Chapter 129
- Tokyo Ghoul Chapter 131
- Tokyo Ghoul Chapter 132
- Tokyo Ghoul:re Chapter 99
- Tokyo Ghoul:re Chapter 46
- Tokyo Ghoul:re Chapter 96
- Tokyo Ghoul:re Chapter 97
- Tokyo Ghoul:re Chapter 98
- Tokyo Ghoul:re Chapter 104
- Tokyo Ghoul:re Chapter 106
- Tokyo Ghoul:re Chapter 107
- Tokyo Ghoul:re Chapter 116
- Tokyo Ghoul:re Chapter 122
- Tokyo Ghoul:re Chapter 139
- Tokyo Ghoul:re Chapter 142
- Tokyo Ghoul:re Chapter 175
- Tokyo Ghoul:re Chapter 178