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|Japanese Name||六月 透 （むつき とおる）|
|Age||19 (Tokyo Ghoul:re)|
20 (after :re Ch. 31.5)
21 (after :re Ch. 73)
|Born||December 14, 17 BSBI|
Mado Squad (Formerly)
Quinx Squad (Formerly)
Hachikawa Squad (Formerly)
S3 Squad (Formerly)
Suzuya Squad (Formerly)
Oggai Squads - Mentor (Formerly)
|Relatives||Tooru Mutsuki's father †|
Unnamed Mother †
Unnamed elder brother †
|Quinque||Ifraft (Rinkaku, Rate B)|
Abksol (Rinkaku, Rate B)
Black Linshing Nut 16/16 (Koukaku, Rate B+)
White Loosting Nut 16/16 (Koukaku, Rate B+)
|Rank||Rank 3 (until :re Ch. 32)|
Rank 1 (after :re Ch. 32)
|Training||2nd Academy Junior|
|Manga Debut||:re Chapter 1|
|Novel Debut||quest: Chapter 1|
"Thinking of their face, whispering 'I love them' under your breath, feeling, in the depths of your chest, a warmth, and yet a tightness... That's what love is, isn't it?"
Tooru Mutsuki (六月 透, Mutsuki Tōru) is a Rank 1 Ghoul Investigator, Quinx, and a former member of the Quinx Squad. Following the Tsukiyama Family Extermination Operation, he was re-assigned to Support for other squads during their missions. He has served as a temporary member of the Hachikawa and Suzuya Squads during major operations. Currently, he acts as a mentor to the Oggai Squads and supports their mission as the Zero Squad.
Mutsuki is a slim, bronze-skinned young adult with dark green hair. He has green eyes, though in his right eye was a permanently active kakugan with a dark gray sclera. As a result, he wore a medical eye patch to cover it but started to wear a leather one after his former mentor Haise Sasaki gives him one as a Christmas present. Like most ghoul investigators, Mutsuki usually wore formal clothing, along with a short, white trench coat. He has a large scar across his upper left pectoral and another across his right side. He also wears a small binder to flatten his chest, held in place with a pair of clips.
He initially had his hair in a bob hairstyle, but after being promoted, he chops it off into a short style.
While being held captive by Torso, his hair gained a lighter color. After Mutsuki regained memories of his past, his hair grew to shoulder-length and turned white.
As Mutsuki intervened in the fight between Takizawa and Amon, his kakugan is no longer in a permanent, activated state. His hair is cut short similar from before and starts to wear plain white clothes more frequently.
After the Clown Siege, his hair grew slightly longer and turned white again.
As a preteen, he wore his hair in a long and fashionable haircut. His eyes appear to have been darker in color, in contrast to how they are shown as an adult.
Mutsuki is kindhearted and gentle but starts off as shy with little self-confidence. Having constant bouts of anemia, ironically, Mutsuki feels repulsed by blood. Due to being sickly and his low self-esteem, he faces discouragement as a ghoul investigator to the point where he feels as though he is not even needed for the job. He expresses frustration with his own weakness, feeling anger at his lack of ability compared to his comrades. However, he is reliable and hard-working, always following orders in contrast to the more troublesome or lazy members of his team. Though lacking in confidence, he shows a strong desire to help others and does not hesitate to place himself at risk to protect the innocent. He eventually gains a boost in confidence and becomes much more assertive. He takes a more active role in having his teammates work together and begins to branch out to other people.
A flashback reveals that he was born female, but unable to reconcile his feelings of discomfort towards his gender. As such, he began living as a man and uses highly-masculine personal pronouns, even when such informal language is not socially appropriate. It contrasts strongly with his gentle personality, and his consistent respect towards others. He shows great respect to Sasaki and Dr. Shiba, as well as other investigators even when treated poorly by them. He is also a confidant to his superior, as he always reassures him when he is feeling down, thus showing a great fondness and admiration for Sasaki.
It is eventually revealed that Mutsuki suffers black-out episodes, leaving gaps in his memories. During these episodes, his personality traits significantly change and frequently involve extreme acts of violence. Afterward, he retains no memory of these actions and denies any accusations involving them. After hallucinating the events of those lost memories, Mutsuki reacts with horror and disgust. However, during his battle against Takizawa he becomes merciless and cruel, expressing arousal when he crushes the latter's testicles. He also severely wounds Akira when she protects Takizawa from his attacks.
After the Clown Siege, Mutsuki's personality becomes very unstable and violent as he becomes obsessed with killing Touka — even willing to harm an innocent citizen associated with her.
Tooru Mutsuki grew up as one of two children, in a household dominated by her abusive father. On one occasion, she was beaten and nearly drowned in the bathtub as punishment for looking at her father with a "disrespectful" gaze. Her mother watched without attempting to help, and she was only released after repeating the line that her father was the best. Afterward, Mutsuki's father leered at her wet shirt while she cowered on the floor.
At the age of 12, Mutsuki was orphaned in a violent incident and taken into the care of the authorities. Though labeled as a ghoul attack, in truth Mutsuki had killed her entire family with an axe during an apparent psychotic episode. Afterward, she retained no memories of the event and continued to insist on the lie that a ghoul was responsible for the carnage.
After her care was transferred to the CCG, Mutsuki formally requested that she be allowed to live as a man. Assuming a male identity, he was sent to attend the Academy Junior School attached to the 2nd Academy, a facility with a reputation for housing troubled young wards. There, he would become the subject of considerable rumors and bullying by his peers. During his time there, he began to harm cats in the woods surrounding the facility. Goumasa Tokage discovered his deeds, but the instructor encouraged his crimes and coached him on how to care for knives. Rumors concerning Mutsuki's crimes continued to follow him, though he denied any knowledge of them when confronted.
Much later Mutsuki would be taught by Haise Sasaki who was working in the academy as a part-time teacher.
Mutsuki studied and expressed confusion over the work. He resolved to ask his teacher, Sasaki, about it the next day.
He visited Dr. Shiba to have his blood drawn, as he had been suffering from a bout of anemia. He admitted to feeling unfit as an investigator but hoped to at least be useful to his comrades. The doctor and patient briefly discussed his teammates, who he felt simply did whatever they wanted without regards to others. As he departed the office, he ran into members of Take Hirako's team and was intimidated into apologizing to them before rushing off. The other investigators briefly discussed him, expressing negative opinions of the Quinx Squad.
Later that day, he met with Sasaki to report the outcome of his recent investigation with Saiko Yonebayashi. A woman had heard growls in her neighborhood and feared it would be a ghoul, but Mutsuki reported it turned out to be only a stray dog. He then reported that Kuki Urie and Ginshi Shirazu had gone off on their own to investigate the ghoul known as Torso, prompting his superior to worry for their safety. The pair located and spoke to Shimoguchi, requesting he share information on the Torso case. The other investigator refused and humiliated Sasaki in front of his subordinate, though Mutsuki was quick to reassure his mentor that he "looked cool." They were later able to track down Urie's whereabouts, arriving just in time to assist in the capture of a ghoul. However, an argument broke out between Sasaki and Urie, and the team again split up.
In a meeting with Dr. Shiba, Sasaki discussed the results of Mutsuki's latest tests. His Rc levels were found to just barely be above those of a human, and he was noted to be unable to control his kakugan. As a result, they worried he would not be useful for the primary purpose of the Quinx project.
That evening, Mutsuki greeted Sasaki when he returned to the team's shared home, The Chateau, and relayed the whereabouts of the other members. Sasaki cooked dinner for him, expressed concern on his poor health and watched as Mutsuki ate the meal alone.
Akira Mado's declaration that her team would discover Torso's identity in a single month placed greater pressure on the squad, leading to further tension among their ranks. While Urie and Shirazu investigated on their own, Mutsuki was recruited to help Sasaki in his own investigation – he expressed concern the other had lost it when he declared he would show them all. The next morning, the pair headed to Cochlea in order to speak to Donato Porpora and gain his assistance in the case. The ghoul briefly turned his attention to Mutsuki, threatening and frightening him as he graphically described his desire to eat the young man. After they departed the prison, Mutsuki wondered why such a dangerous ghoul had been allowed to live and mentioned the horrible look in his eyes.
Based upon the information provided by Donato, Mutsuki and his superior spent the following weeks gathering information about the previous victims. From interviewing people who knew the victims, they realized Torso targeted women with surgical scars and connected his hunting grounds to several hospitals. With time running out, they made the decision to split up and canvased the hospitals at the center of Torso's territory. On the twenty-fifth day of the investigation, Mutsuki visited a plastic surgery clinic and witnessed a taxi driver watching a woman with a predatory look. Though ordered not to do anything alone, he rushed over to the taxi and cut in front of the woman. He felt a growing sense of unease, but attempted to make small talk with the driver. However, the driver suddenly turned on him and revealed himself to be a ghoul, attacking Mutsuki while demanding to know "which" he was. The driver climbed into the backseat, and tore open Mutsuki's shirt to reveal his bound breasts.
Torso was excited to find Mutsuki was biologically a woman, and saw the scars on his chest. Mutsuki managed to get his quinque out and briefly fought back, but was overpowered and given a serious beating. Before Torso could do more, he noticed Urie and Shirazu approaching the taxi on a motorcycle – he took off with an injured Mutsuki in the backseat, prompting a chase. Assistance from police units finally ended the chase, and his teammates fought Torso as Mutsuki climbed out of the taxi. He struggled to unleash his kagune, but was unable to do so and was frustrated at his weakness compared to the others. During the Quinx Squad's battle with Serpent, Mutsuki noted they are no match for him, and therefore advised Urie and Shirazu to retreat. After Serpent escaped and Sasaki was shot down by Akira, Mutsuki stood by as he watched Sasaki receive Rc suppressants.
In the Quinx's living quarters, Mutsuki grew furious when Urie insulted Sasaki by calling him a "ghoul." Later on, Mutsuki advised Shirazu to apologize to Urie for attacking him.
Mutsuki was then alongside Shirazu and Sasaki discussing their new target, Nutcracker. Mutsuki informed Shirazu that Saiko would be back at nine o' clock that night. Upon entering the cafe ":re," Mutsuki became puzzled when Sasaki used the term "kagune nose" to represent his ability to determine the quality of the café's coffee.
After the group left the cafe to go home, Shirazu expressed concern over their mentor's odd behavior. Mutsuki agreed and clenched his hands in his trench coat anxiously, but dropped the subject. Back at home, they found Urie had returned and headed upstairs to confront Saiko. While the other two broke down the door and berated Saiko for neglecting her duties, Mutsuki fruitlessly attempted to repair the broken door.
The next morning, the team prepared to head to the 13th ward to meet with Juuzou Suzuya and his squad. While Shirazu tried to wake up Saiko, Mutsuki waited with Sasaki in the car. He began to ask him something but decided against it. During the meeting, he continued to give his mentor concerned looks as the events of the previous day were recalled.
While they waited for their orders, Mutsuki commented about their waitress being very cute. Shirazu agreed with him, prompting him to tease him for having a crush on Akira. When their coffee arrives, he complimented the delicious taste happily. As they drank their coffee, Sasaki began to cry, confusing both of his subordinates and led to them to worry about his odd behavior.
After leaving the cafe, Mutsuki wondered what could possibly have Sasaki spacing out all the time. At the Quinx living quarters, Mutsuki informed the squad of Saiko's arrival and was later surprised when Urie encouraged Saiko to start doing her work. The following day, Mutsuki accompanied Urie and Sasaki to visit the Suzuya Squad concerning the Nutcracker investigation, where he once again noticed Sasaki being inattentive to the discussion.
When he expressed confusion over Suzuya's arrival and unusual method of greeting Sasaki, Hanbee Abara explained the history between the two leaders. Shirazu finally arrived at the meeting and surprised everyone by carrying a still-sleeping Saiko on his back. Mutsuki praised him for actually managing to bring Saiko to the CCG.
The Quinx Squad began their investigation into Nutcracker by observing her at a local cafe, attempting to use their heightened senses to spy on her conversation. When Saiko did not take the mission seriously, Mutsuki played referee between her and a highly-annoyed Shirazu. Unfortunately, Shirazu knocked over a glass and drew attention to himself, causing their target to leave earlier than expected.
Later that evening, he listened to Shirazu's concerns about being a poor leader. Mutsuki reassured him that he was doing well, and revealed that Urie lied to Saiko about the details of their contract. He suggested they keep this to themselves, and puzzled over Sasaki allowing Saiko to neglect her work all the time.
The investigation uncovered an upcoming auction, and the team decided to use the "ingredient" list in order to get closer to Nutcracker. For this purpose, Sasaki ordered the team to go undercover at a nightclub, disguised as a group of young women. Mutsuki was extremely uncomfortable with this turn of events, and was overcome with anxiety at the thought of strange men staring at him. He ended up accepting a drink from a waiter and quickly became intoxicated. This loss of inhibitions led him to approach Nutcracker directly, complimenting her hair and chatting with her until she offered him a part-time job – actually the lie used to lure victims to the auction.
Having completed their mission objective, he rushed back to the others to report it. Sasaki attempted to berate him over drinking, but Mutsuki ignored this and announced his intention to celebrate by dancing. Shirazu and Saiko joined him, while Sasaki watched them from a distance.
With the time and location for the auction obtained, Matsuri Washuu met with Sasaki and Suzuya to discuss the operation. He decided to use Mutsuki as bait for the upcoming operation, ordering Sasaki to send him in undercover and alone. Suzuya intervened, offering to accompany Mutsuki so there will be a second person inside during the operation. Sasaki was relieved and entrusted Mutsuki's safety to Suzuya.
Later that night, Sasaki struggled to maintain his composure while informing Mutsuki of his role in the operation.
Mutsuki was seen being trained by Sasaki along with his teammates. Sasaki was disappointed with the results of their attacks against him as they were armed while he was not.
A week prior to the Auction Mopping-up Operation, Mutsuki met with Suzuya to prepare for their infiltration. To train him, Suzuya demonstrated how to juggle knives while attacking at the same time, something Mutsuki did not feel he could ever accomplish. He wondered whether Suzuya was ever afraid of being injured by his knives, and admitted to being afraid after seeing Sasaki lose control of his powers. He clarified that he did not actually fear his mentor, but rather feared to suffer the same fate. Suzuya advised him that fear could be a good or bad thing, depending on his ability to overcome his own weaknesses. Mutsuki took these words to heart.
Auction Mopping-up Operation
On the day of the auction, many investigators gathered in preparation for the operation. Mutsuki, again disguised in women's clothing, was joined by a similarly disguised Suzuya. The Quinx Squad saw him off, and the pair met with Nutcracker to head to the auction site.
Some time later, Mutsuki awoke confused and disoriented. He drifted in and out of consciousness but recalled that some sort of gas was leaked into the vehicle during their trip. Once he fully recovered, he attempted to contact the CCG with a small device but could not reach anyone. He realized he might be out of range, and had no idea whether anyone knew his location.
Eventually, Nutcracker came to fetch him and roughly threw him onto the stage. The auctioneer, Uta, announced this was a last-minute addition and the asking price would normally be 1 million – however, this was not the case. A spotlight was focused on Mutsuki as he struggled to regain his bearings.
Realizing he had become merchandise for the auction, Mutsuki's thoughts raced. Uta made a show of getting into his personal space and noted his unusual scent before stealing his eye patch – exposing his active kakugan to a shocked audience. Mutsuki cowered and tried to hide his eye, but the shock of a rare one-eyed ghoul being offered for sale sent the crowd of ghouls into a frenzy of excitement. The starting price was set at ten million but rapidly climbed as Mutsuki quickly began to panic. His thoughts became a chaotic mess, alternating between thoughts of fighting and wanting to be saved.
Just then, Uta touched him on the shoulder and whispered something to him. Mutsuki fell silent and meekly sat until the fierce bidding war between Kanae von Rosewald and Big Madam concluded in the Madam's victory. He was sold for a record 200 million yen, and escorted away by Nutcracker. The ghoul was so delighted with how valuable he turned out to be, that she gave him a celebratory kiss on the check.
As the operation began, it was noted Mutsuki had failed to contact them, leading to speculation that his transmitter was broken. With the auction house in chaos, Nutcracker attempted to make off with her "200 million", drawing the attention of Torso in the process. However, Mutsuki managed to kick his captor down and escape, taking refuge in a supply closet to gather his thoughts. He thought back to Uta's words, recalling how he had despaired upon being told the mission was a failure and no one would come to rescue him. He tried to make sense of it, realizing someone knew about the operation but apparently allowed it to happen anyway. But before he could think about this further, he was greeted by Kanae – who had decided to steal the "prize" for his master.
Cornered, he recognized the ghoul as one of the people involved in the bidding war. Kanae decided he needed to confirm Mutsuki's taste, striking him hard enough to draw blood and licked the drops from his hands. Just like Kaneki, the taste of his blood proved to be incredible, bringing Kanae to tears at having finally found the unique flavor for his master. But before he could attack Mutsuki again, Torso arrived and began beating him. Frightened by the violence and recognizing him, Mutsuki tried to flee the room – a desperate, wounded Kanae impaled him through the stomach with his kagune to keep him from escaping.
Some time later, Mutsuki stumbled down a hallway while bleeding profusely. He wondered whether his wounds would even heal, and recalled how he was bullied at the Junior Academy in the past. Concluding his life has been miserable, he thought about meeting his family again. His wanderings eventually led him into a hallway filled with the bodies of dead investigators.
Later, he recovered somewhat from his injuries. Kanae managed to locate him, and launched an attack with his kagune but Sasaki managed to pull Mutsuki to safety at the last second, while Urie and Shirazu fought. After Kanae and Matsumae retreated, the team reported back to command and learned that Nutcracker has eliminated the Ooshiba Squad. Sasaki requested for Mutsuki to be allowed to retreat and receive medical treatment for his injuries since they prohibited him from fighting against an S-rated ghoul. Matsuri agreed to this and ordered Urie to handle the escort – something Urie initially fought against. Sasaki praised Mutsuki for his hard work and entrusted him to Urie's care. As the pair retreated, Mutsuki inquired about Urie's isolation from the rest of the team and suggested he was someone that others would like to be able to rely upon. Urie brushed these statements off and claimed to have gotten lost. Under this ruse, he instead went to investigate the main hall and encountered a secret passage. Down below, they discovered the auction guests' hiding place and were quickly joined by Juuzou Suzuya. Urie again lied, claiming to be unable to contact anyone and suggested they attack.
While Suzuya and Urie fought down below, Mutsuki provided support from above. He managed to fend off and kill two members of Aogiri Tree before using his vantage point on the catwalk to locate Big Madam. He shouted this information to Urie, who charged off alone. By the time Mutsuki was able to catch up to him, Urie had already been defeated and was being swallowed whole by Big Madam.
Mutsuki rushed to help but came under attack by Madam's bodyguards. He was unable to fend them off and collapsed from several knife wounds while Urie went berserk and freed himself. Completely out of control, the other man killed the bodyguards and attacked Big Madam again, but was defeated and collapsed to the ground while ranting about his hatred for the other Quinx. Mutsuki moved towards him and was impaled through the stomach by Urie before he came back to his senses. Though injured, Mutsuki brought out his kagune for the first time and offered words of comfort to the other. Urie realized the scent of blood was from menstruation rather than an injury, expressing confusion over this while Mutsuki remained silent. The pair was interrupted by Big Madam, who prepared to attack them. Suzuya and his squad arrived and surrounded Mutsuki and Urie in preparation to fight the ghoul.
After backup from the CCG arrived, Mutsuki quietly sat beside Urie with his head hung downwards.
A month had passed since the Auction Mopping-up Operation and Mutsuki was helping Sasaki prepare for a Christmas party. He took inventory of the pantry and asked Urie to do the grocery shopping. He refused, but then reluctantly agreed due to Mutsuki's insistence. That night at the party, he received a leather eye patch as a gift from Sasaki.
Spring arrived and it was time for the CCG's award ceremony. Mutsuki was awarded a double promotion, from Rank 3 to Rank 1, for his exemplary performance during the Nutcracker investigation and the Auction Mopping-up Operation. At the after party, he wondered if he was worthy of the position. Iwao Kuroiwa also made an appearance at the party and Mutsuki was in awe he continued as an investigator despite losing an arm.
Some time later, Matsuri held a meeting about evidence found after the auction suggesting the Rosewald family still existed and may have been responsible for the kidnappings. The evidence was based on kagune markings left on quinque and how they had certain similarities. After the meeting, Mutsuki questioned Sasaki about kagune matching among relatives.
Mutsuki was among the investigators observed by Shuu Tsukiyama who constantly interrupted his attempts to speak privately with Sasaki. To this end, Kanae hired several members of Aogiri to eliminate Mutsuki and his comrades.
The Quinx entered a parking garage to investigate, and were ambushed by Kanae. While Urie and Shirazu were lured away, the others were attacked by a group of ghouls led by Hooguro and Shousei. Sasaki ordered Mutsuki and Saiko to find the others, realizing they had fallen into a trap. As Mutsuki attempted to catch up with the others, Torso appeared before him and attempted to flirt. In response, Mutsuki ordered Saiko to escape and attacked the ghoul – displaying a significant increase in his strength and fighting prowess. Torso was thrilled by this change, even as Mutsuki continued to attack him.
Grave Robber intervened, blocking Mutsuki's strikes with a quinque sword. The two fought each other, proving evenly matched and blocking each others' strikes. Mutsuki unleashed his kagune in an attempt to overwhelm his opponent, disarming the ghoul and moving in for the kill. However, Grave Robber expressed amusement at facing another bikaku and used her own kagune to drive Mutsuki back. She retrieved their quinque and Mutsuki braced for the finishing blow but was rescued by Urie. Faced with three Quinx, the ghoul retreated and Mutsuki led the others back to Sasaki. They were shocked to see him fighting with both quinque and kagune, slaughtering his multiple opponents effortlessly. As the survivors were driven off, the squad hurried outside to help Saiko and found her alone in the alleyway.
One day, after Shirazu decided to cut off all his hair, Mutsuki asked with some worry as to who cut it. Later on, he was present during a meeting on how to deal with the Rosewalds where he sat next to Saiko and tried to keep her awake. He quietly listened as Sasaki requested he and the squad take advantage of their ghoul-like features to gather intel from the ghoul world.
While wearing his ghoul mask, Mutsuki overlooked the city along with the Quinx Squad looking uncomfortably at Sasaki's leather eye patch mask. He was paired with Urie to get information from ghouls, difficult since most avoided the pair. When Sasaki asked if they let the ghouls escape, Mutsuki answered quietly that they did and looked surprised by Saiko's comment that some ghouls seemed good. Shirazu asked Sasaki how he was doing and as their mentor nervously laughed he was not doing well, Mutsuki looked confused at his answer.
Mutsuki accompanied his squad to the Tsukiyama Estate, where they waited for further instructions on the raid. After being informed that the Tsukiyama head surrendered peacefully, they relocated to the Luna Eclipse where the Tsukiyama family's heir escaped to. Midway through fighting in the tower, Sasaki was sent to the building rooftop via the building's exterior and the rest joined with the Itou Squad.
The SS~ rated ghoul, Noro, was encountered by the joint squad soon after, to which the squads suffered heavy casualties due to the ghoul's insane power and extreme regeneration abilities. After Noro was blown into pieces by Shirazu's Nutcracker quinque, rampaging kagune limbs emerged from the separated lower half and disabled all investigators on the scene but Shirazu and Saiko, who was resting in the back after using her kagune. When Mutsuki came, he was asked by Takeomi Kuroiwa if he was okay to which he replied he was and looked at his fellow Quinx members crowding a bit away from him confused, unsure of what happened. After hearing Urie screaming at Shirazu to not die on him, Mutsuki was shocked as he finally understood why they were crowding there yelling. He later mourned Shirazu with the rest of the squad.
Mutsuki visited Shirazu's grave with the other Qs. Akira comforted a sobbing Saiko, Urie wandered off, and Sasaki did not come. He went to confront Urie and asked if he was going to the grave; he refused to do so, stating Shirazu was not buried there and vowed to find his body, as it was stolen by Aogiri after the operation.
Six months after the Tsukiyama Family Extermination Operation, Mutsuki left the Quinx Squad and was transferred from squad to squad as support. He assisted Hachikawa Squad led by Chuu Hachikawa on a mission to inspect a possible Aogiri Tree hideout on Rushima, uninhabited since World War II. There, he and the Hachikawa Squad encountered Aogiri grunts and easily disposed of them. Mutsuki noticed Scarecrow leaving alone on a paddle boat and wondered if he was a member of Aogiri. He was smacked on the back of the head by Hachikawa who accused him of spacing out and they moved on. They eventually found Aogiri's hideout and spy as Eto delivered a speech to the Aogiri members, but were spotted by Owl. Having alerted the ghouls, they made a run for it, but Owl intercepted them.
Mutsuki was shocked when Shikorae bit off Hachikawa's nose and held Ayumu Hogi back when he was killed. Shikorae then launched ukaku projectiles at Mutsuki and Hogi, but Mutsuki deflected them with his kagune and jumped off a cliff into the water to escape. Shikorae and Owl gave up on chasing them, opting to eat Hachikawa instead. In a cave, Mutsuki did his best to patch Hogi's arm having been injured by one of Shikorae's projectiles. He said since they determined Aogiri's stronghold was on Rushima, they could retreat, before consoling Hogi about Hachikawa. Hogi told him about Hachikawa's past and why she liked him, that no matter who the person was, if there was one beautiful memory of them, it was hard to feel disgusted. Mutsuki thought about Sasaki and how much he had changed, sympathizing with Hogi.
However, Torso ambushed them. He grabbed Hogi's hair, bashed her against the cave wall and then tossed her aside, leaving Mutsuki horrified. As he yelled out Torso's name he was grabbed by the throat and Torso leaned in, asking if Mutsuki came to see him.
Mutsuki woke up tied to a chair and Torso greeted him, telling him it was their "secret home" and they were getting married. Mutsuki did not reply when Torso said he was unsure why he was attracted to Mutsuki, who tried to think of a way to escape if only he could move his hands. However, he realized his limbs had been cut off and began to scream hysterically.
Rushima Landing Operation
Five days after the invasion of Rushima began, Mutsuki was brought a gift by his captor. Torso praised him for being cute, gifting him with a hand-made flower crown. When Mutsuki glared at him, causing Torso to fly into a violent rage and beat him while screaming insults. This brought back memories of his abusive childhood, and the actions of his father. Some time later, the two bed down on make-shift futons. Torso claimed he only punished his "lover" because of his deep love, and asked whether Mutsuki was happy. Still bruised from the earlier attack, Mutsuki told Torso what he wanted to hear while thinking about how he was cursed.
Some time later, Mutsuki dreamed about being interrogated over the deaths of his family. He woke up in tears and found Torso watching him sleep. Mutsuki requested food and turned the topic of conversation towards their memories of their past. He confessed there were pieces of his memory that seemed to be missing, leaving him unable to recall events. In order to avoid any further harm, Mutsuki asked about Torso's past and learned about his horrifying childhood. Afterward, he lied awake and struggled with feelings of sympathy towards his captor.
Torso suddenly came up behind him, picked Mutsuki up and carried him out of the cave. As Mutsuki was carried off, he noticed several pairs of scissors tucked into Torso's tool belt. Convinced he was being taken away to be killed, Mutsuki struggled and fought to escape. In the ensuing struggle, his head was struck against a rock and he lost consciousness.
Mutsuki "wakes" up in a dream-like state, witnessing the events of his past play out in front of him. He witnessed his younger self murder his family, killing a cat at the Academy, and followed himself through the halls of the auction. Behind a closed door, he witnessed himself eating from the corpse of an investigator to heal his injuries. The floor beneath his feet gave away, and Mutsuki fell into darkness as he processed the horrifying revelations about his own past. He referred to himself as disgusting and decided he should allow himself to be killed by Torso.
However, when Mutsuki regained his awareness, he discovered he was back in the cave, his limbs had fully regenerated, and was horrified to discover himself holding a severed forearm in his hand. As he threw it away from him in disgust, he fell to the ground and saw the mutilated remains of Torso propped up in the seat he himself had been kept in during his imprisonment. Mutsuki recalled that Torso took him to a flower field as a surprise, and he killed the ghoul by cutting his head off. Realizing the truth of his own actions, Mutsuki collapsed and began laughing insanely.
Having made his way to the fight with between the Owl, Seidou Takizawa, and Floppy, Koutarou Amon, Mutsuki questioned Akira if reinforcements were coming. Akira confirmed that both Suzuya and the Quinx squads were coming. Hearing this, Mutsuki had decided to hold off Owl until backup arrived. When engaging Takizawa, Mutsuki had managed to stab him through the abdomen. Taking advantage of this, Takizawa used it to pull Mutsuki towards him and pierced him through the stomach. While mocking his opponent's strange expression, Mutsuki spit a mouthful of blood into his face. While Takizawa was momentarily blinded, Mutsuki took advantage of this, kicked him between the legs, and knocked him to the ground — he was then quickly pinned down by Mutsuki's tails. While Mutsuki was preparing to finish him off, Akira went between the combatants and shielded Takizawa. Taken aback by Akira's actions he stabbed her again. After realizing his former superior violated the Ghoul Countermeasures Law, he repeatedly lashed at Akira with his kagune. He listened as Akira confessed her feelings to Takizawa, and was ready to attack again when Amon interferred ― his quinque connected with Mutsuki's face, and the two fought. His kagune overpowered and wounded after being bitten in the shoulder, Mutsuki was not faring well in the battle, and was saved by the arrival of the Quinx Squad with Urie in the lead.
Urie's first priority upon entering the scene was Mutsuki's wellbeing. After Mutsuki updated Urie on the current situation, he decided his course of action and fought with the ghoul. After nearly defeating him, Saiko attempted to attain ownership rights of Floppy, however Urie's passionate words against ghouls stopped her and arose an emotion in Mutsuki akin to either shock, fear, or worry. They initially wondered if they had finally killed the ghoul after a powerful attack from Ginkui, however, Floppy instead donned a deformed kakuja armor. After the leaders of the Quinx Squad had been injured, Higemaru asked for Mutsuki's assistance before fighting Floppy. Higemaru temporarily tied the kakuja ghoul down with his kagune and Mutsuki used his own to attack and cried out when Higemaru was smashed into a wall before Mutsuki himself got hit and bitten again. This enraged Urie, who stood to once more land another blow to their opponent as Mutsuki was thrown to the side. Afterwards, Saiko supposedly crushed the ghoul following Urie's second injury.
Being apart of the CCG's survivors on Rushima, they received Matsuri's transmission via radio of the "ambush" of Yoshitoki Washuu, and the false report of Itsuki Marude's suicide, as well as Kishou Arima's death during the breach of Cochlea by the hands of Sasaki.
Post-Rushima Landing Operation
A month after the operation's conclusion, Mutsuki was in Saiko's company when Urie questioned their progress in the search for Sasaki. When asked directly, Mutsuki replied that he had a lead he had already looked into while thinking of his past visit to :re with Shirazu and Sasaki, but instead of relaying his thoughts, he stated he found nothing of use. After leaving with Hsiao, Saiko commented about Urie's growing strength. When Saiko asked if she was the only one feeling gray, Mutsuki said he believed in Sasaki, since he surely had a reason for his actions and mentioned how nice Sasaki was to them all when he was their mentor. Moments after, Saiko hesitantly asked Mutsuki what he was hiding from them. Mutsuki's face was shocked but still shared with her that he was born a girl and was about to add to his words before Hogi arrived and he left with her.
During the Clown Siege, Mutsuki and Shinsanpei were ordered to hold the front line with Suzuya Squad. Following the arrival of a large horde of Clowns, Mutsuki took down several of them in succession before providing cover for Keijin Nakarai. Seeing Shinsanpei, Mutsuki advised him to cut deeper, encouraging him.
As the battle was reaching its close, Uta fled from his fight with Suzuya and Mutsuki chased after him. He eventually followed him to a secluded area and tackled Uta to the ground. He laughed as he stabbed him numerous times but stopped just before Uta changed his face to that of his former mentor, Sasaki.
Mutsuki immediately calmed but after being asked to let his victim go, he brought his quinque down into "Sasaki's" throat. While begging him to not leave again, Mutsuki stabbed him frantically in the face until it was deformed. He confessed his love for his mentor before embracing him and was found by Shinsanpei straddling "Sasaki."
Shinsanpei denied seeing anything after Mutsuki put a coat around himself. Shinsanpei shared his wish to kill Sasaki and Mutsuki approached him and suggested they kill him together.
Some time after, Mutsuki was in attendence when Kichimura Washuu was officially named the CCG's new bureau director and a new squad was introduced. The Oggai Squads' debut included the beheading of Sasaki, really only a double, causing Mutsuki to only look indifferently to the side,  or look on in horror.
Mutsuki approached Takeomi Kuroiwa and asked about the photo he had of Yoriko Kosaka and her friend, whom he recognized as the waitress from :re. Takeomi told him he wanted to invite her to the wedding so Mutsuki asked to borrow it, giving only an opaque explanation that he possibly knew her.
At some point, Mutsuki copied the photo and stabbed them onto the wall of his room. All into the left side showing Touka's face. They were later found by Urie when he entered Mutsuki's room after a bagged box was delivered to him.
After, Mutsuki and Shinsanpei went to visit :re. As Kaneki was ready to close the front door, Mutsuki entered the shop and grabbed onto his hand. Mutsuki immediately expressed his refusal to believe his mentor had died and attempted to persuade him to come back, offering to do anything. However, he was refused at the same moment he spotted Touka behind the cafe counter.
Mutsuki changed his demeanor and commented on the scent of ghouls in the shop. He deliberately mentioned Kaneki's betrayal, both of the CCG and those who knew him. Then he sliced the left side of Kaneki's face before once again telling him to come back to him. Mutsuki continued his attack, slicing at him — enjoying the sound of his mentor's voice — and stabbed through his arm, entering the Rc suppressants from his quinque into Kaneki. As his attacks were dodged, Mutsuki resorted to his kagune and sent Kaneki out the window onto the street outside and had Shinsanpei appear.
After Touka had moved forward, Mutsuki sent a kick her way only to have it blocked. Taking further action, Touka sent a barrage of ukaku shards from above at Mutsuki. He dodged each of them and replaced Touka as the offensive. He frantically called her a cat while attempting to cut at her with his knives but she evaded each. Their skirmish continued before Mutsuki surprised Touka by swinging around her to hook his arms around her neck and choke her. He was then impaled by her kagune and sent to the floor.
Standing, Mutsuki told her he hated women and had come to see her. He held up a detached hand along with the photo given to him by Takeomi, informing Touka that Yoriko was getting married. Mutsuki's attempt to get Touka to comply with his demands failed when she instead kicked him in the face, sending him across the floor, denying having ever known Yoriko.
After the Oggai made an appearance, Mutsuki watched in anger as Touka and Kaneki escaped over a nearby building and yelled for the squad to pursue them. He did not want Kaneki to go and screamed he would kill Touka just before setting the shop ablaze and weakly called for his former mentor.
At an unspecified time, Mutsuki was called in by Kichimura Washuu and was selected to be the training supervisor for the Oggai Squads. Considering it an opportunity to the top, he accepted. With it came the chance to participate in the top CCG missions, including those concerning Sasaki.
Mutsuki was later a guest at Takeomi and Yoriko's wedding. Afterwards, he sat with Urie, who had also been there, but Mutsuki had not expected him to. Mutsuki questioned if they would be able to have the happiness he saw in Takeomi, before joking with Urie the likelihood Saiko would be a mom or wife. He stood after Urie said he could come home every so often. He mentioned his visit to the cafe Sasaki frequented that resulted in meeting the man himself. Mutsuki then explained to Urie what he wanted — to have them all together again. He spoke about his new position as the Oggai squads' mentor and teared up as he explained his actions as things he was just unable to help doing because of the love he had for Sasaki. Finally, Mutsuki walked away from Urie.
From their first meeting, Mutsuki recognized Sasaki as the part-time instructor from the CCG Junior Academy, therefore Mutsuki refers to him as sensei. Mutsuki looks up to Sasaki as his superior, and even views him as a close friend. Though he may be timid around other ghoul investigators, Mutsuki is often very comfortable around Sasaki. Unlike the other members of the Quinx Squad, he is very loyal, to the point where he prefers to accompany Sasaki on a mission, rather than to do it independently without his mentor’s consent. Mutsuki is also shown to have concern for Sasaki's well-being, but would not hesitate once an order is given. He respects Sasaki to a great extent, as seen when he becomes furious after witnessing Urie insult Sasaki. Mutsuki admitted that he is afraid after seeing Sasaki losing control; not because he fears his superior but rather he fears losing control the same way.
Even after Sasaki left the Quinx Squad, Mutsuki still cares about him as shown in his conversation with Hogi. Hogi reminisced about Hachikawa and said that if you had one beautiful memory of a person, it is hard to feel disgusted for them. Mutsuki thinks about how much Sasaki has changed, saying that he possibly understood Hogi's feelings.
After learning of Sasaki's defection from the CCG, Mutsuki never expresses any ill-will towards the former and knew he had his reasons. This however is proven to be just another false impression Mutsuki tries to pass on to others. In secret, he harbors intense romantic feelings for his former teacher on a pathological level. He was extremely jealous when he witnessed Touka handing Sasaki her handkerchief when his eyes swelled with tears. In a fit of madness he proceeds to violate Uta after frantically stabbing him on the face and throat, thinking it is Sasaki. His obsession has grown to the point where he declares that as long as Sasaki doesn't belong to anyone else, he doesn't care about what happens in the end.
Mutsuki and Urie were often not on good terms, due to their differences in approach towards Sasaki. He often grows worried whenever there is a dispute between Urie and Sasaki, and even becomes angry to see Urie insult Sasaki. However, Mutsuki is still somewhat concerned for Urie, as shown when he insisted that they retreat during the battle against Serpent, and even asked Shirazu to apologize for kicking Urie. During the auction, they end up paired together and Mutsuki comforts an out-of-control Urie at the risk of his own life. As a result, both are now aware of a significant secret. Mutsuki's shown to be working alongside him even more than before.
They had a close friendship, frequently joking around and spending their free time together. Mutsuki's more gentle and observant personality worked well with Shirazu's more aggressive nature, making them good friends that were able to balance each other out. He frequently acted as a mediator between Shirazu and the others when he lost his temper, helping to smooth out disagreements before they could cause problems within the team. He also served as Shirazu's primary confidante after being promoted to squad leader, listening to his worries and offering reassurances or advice. Shirazu showed a protective streak towards him, while Mutsuki compared himself negatively to his stronger comrade in terms of fighting ability and powers. Like the rest of the squad, he mourned him greatly after he passed away.
The two have worked together on an investigation in the past and seem to be on good terms. When her actions cause friction in the group, Saiko looks to him to act as a mediator and defend her from Shirazu's wrath. Mutsuki expresses concern over how her actions have caused them all stress, and wonders if there is a larger reason for their mentor allowing Saiko to slack off so much, also Saiko once mentioned she smelled human blood on Mutsuki. According to an omake, he spies on Saiko's Twitter account to find out when she was ditching work and is often the one to pass news about her to others.
The murderous ghoul attacked and attempted to kidnap him, resulting in the ghoul's identity being exposed. Mutsuki noted that Torso's expression was that of a predator, and had an instant sense of unease upon seeing him from a distance. His intuition proved to be correct, and he was forced to fight for his life against the ghoul. Mutsuki expressed distress at his own weakness, having to be rescued by his comrades and unable to help them fight. Since their encounter, Torso had become obsessed with him and shifted from hysteria to extreme violence when Mutsuki was in danger, later, when Torso captured Mutsuki, he went as far as to claim they were getting married.
As Mutsuki uses dagger quinque, Suzuya became a mentor of sorts to him being proficient in dagger use himself. Their relationship started out as strictly professional, but Suzuya's surprising wisdom helped Mutsuki gain more confidence. Suzuya has become a person Mutsuki trusts and confides in and after the Auction Mopping-up Operation, their friendship took off. Suzuya and his squad appear to be some of the few people Mutsuki associates with recreationally aside from the Quinx Squad.
The leader of the Hachikawa Squad. He did not seem to have much respect for Mutsuki, dismissing his abilities and easily became frustrated with him.
However, after Hachikawa was killed by Shikorae and Takizawa, Mutsuki admitted that he thought he was excellent.
The two seem to work well together and respect each other on a professional level. Mutsuki listened to Hogi after she lost Hachikawa and did his best to comfort her.
Mutsuki initially acts as a mentor to Aura. As Aura begins to reveal his thus far quiescent depravity caused by Ken Kaneki he starts to exterminate ghouls more brutally and Mutsuki encourages and tutors him in his actions. In a similar dynamic to Tokage's mentoring in torturing animals to Mutsuki, Mutsuki instructs Aura to "cut deeper" when killing. Aura admires Mutsuki, and when she is caught raping Uta's body he covers for Mutsuki and they keep the secret together in an alliance.
Mutsuki harbors a grudge for Touka due to his feelings of love towards Sasaki. Takeomi Kuroiwa asks Mutsuki to find Touka as a favor to Yoriko, and gives him a photograph of Yoriko and Touka. Urie enters Mutsuki's room and finds copies of the photograph stabbed into the wall with knives, with the blade through Touka's face. Mutsuki tracks down Kaneki to Touka's coffee shop, where he attacks them, showing that he has a deep hatred for Touka. These feelings only escalate when Tooru discovers that Kaneki and Touka are married.
Powers and Abilities
Like all members of the Quinx Squad, Mutsuki received preliminary training in combat and investigative procedures. His body surgically modified with the intention of granting him abilities similar to a ghoul. In the beginning, he was unable to use his kagune and lacked the superior physical abilities of his peers nor could he wield his quinque well. He did, however, show a decent level of regeneration. A short time after being stabbed through his arms by a kagune, he used them without significant impairment. He possessed exceptional eyesight, able to make out details from long distances even though his right eye was usually covered by an eye patch.
After the Auction Mopping-up Operation, he is able to summon his kagune properly and has become all around much more skillful. Some time after being promoted to Rank 1, he learned to control his kagune and improved on his dagger wielding after being taught by Suzuya. He improves so much that Sasaki, who at first was concerned that Mutsuki was not cut out to be an investigator, now defends his status and places him in the front of formations with Urie. Considered very agile and is relied on to close in on dangerous enemies quickly.
Quinx Physiology: After his body was surgically modified, Mutsuki possesses a bikaku kagune and increased physical abilities.
- Bikaku Kagune: His kagune possesses several segmented edges. He is able to extend it to long distances and use it to block, make powerful attacks, or to bind an enemy. At first, he was only able to manifest a single kagune, but after his experience with Torso, he is now able to produced several kagune tails. During the Goat Wipeout Operation, he displayed his ability to shape his kagune into a cocoon as a form of insulation against Yomo's electrokinesis. During the Defense of Tokyo, it is revealed that he is able to trace the kagune formations of others and use their own kagune against them.
- Kagune Detachment: Mutsuki has shown to be capable of detaching fragments of his kagune, applying his knife-throwing skills.
- Superhuman Durability: Mutsuki was able to take Urie's attack directed at his abdomen without flinching.
- Superhuman Regeneration: After receiving critical wounds, Mutsuki displayed the ability to regenerate and recover from them at an inhuman rate.
- RC Control: Mutsuki has developed a method of concealing RC levels within the body, causing standard methods of detection to fail. Dr. Shiba theorizes that this ability involves suppression of the RC cells, as blood tests gave back an impossible RC level of 3; even for humans, the average RC cell count is 200-500. As a result of this ability, the CCG researchers have been unable to make an accurate assessment of Mutsuki's physical condition. 
Ifraft and Abksol: These quinques are a pair of daggers made from rinkaku kagune, and wielded together. Though they lack range, in close quarters they are shown to be extremely sharp and capable of easily slicing through a ghoul's flesh and bone. After receiving guidance from Suzuya, Mutsuki has shown to utilize the same knife tricks efficiently, albeit to a lesser extent.
Scorpion 1/56: This quinque is a small, flat-tipped switch blade that can be used for multiple purposes, they are deadly and efficient. Mustuki is able to throw this quinque at from a far distance with quite amount of potiency to make the likes of Seidou Takizawa scream and curse in pain upon being stabbed in his eye. It is unknown if Mustuki possesses the full 56 set.
Black Linshing Nut 16/16 and White Loosting Nut 16/16: A quinque in the form of a pair of thirty two koukaku utility knives. Mustuki is able to throw this quinque at from a far distance with quite amount of potiency.
- Mutsuki was ranked twenty-second in the latest character popularity poll.
- Mutsuki has numerous traits in common with Kaneki at the beginning of the original series, including his meek personality and difficulty controlling his powers.
- The two share a similar past experience, Kaneki had an abusive mother, implied that she beat him when he was asking for things. Mutsuki's father abused him by hitting him or drowning him and is hinted to have sexually abused Mutsuki.
- Kaneki's hair turned white as a result of the torture he received from Yamori. Mutsuki's hair began to whiten after having been held captive by Torso and having his limbs cut off, and turns completely white after regaining his memories about the black-out episodes.
- Others refer to him as "Eyepatch-kun," the alias once given to Kaneki.
- During Mutsuki's time as Torso's captive, he began to sympathize with Torso after hearing his history, this is a sign of a psychological phenomenon known as Stockholm Syndrome.
- His kakugan is permanently activated. In :re Chapter 92, his kakugan is no longer permanently activated.
- He dislikes rare cooked meat.
- In contrast to his gentle personality, Mutsuki uses the personal pronoun ore (俺), usually reserved for male characters that are tough or aggressive but can also be used by girls with a tomboyish nature, which is referred to as Ore Onna.
- When nervous or upset, he has a tendency to grab onto the fabric covering his lap and wring his hands.
- He is ambidextrous, and one of the few investigators shown dual-wielding.
- According to Shirazu, he is the only member of the Quinx that can cook when Sasaki is unavailable.
- Mutsuki has been associated with the Tarot cards The Wheel of Fortune and The Chariot.
- Mutsuki was rumored at the Academy to have killed a cat, something people said Suzuya had done as well.
- This was confirmed in :re Chapter 79, having stuffed the cat's remains in a jar and later buried it.
- For his contribution to the Auction Mopping-up Operation, Mutsuki is awarded a two-rank promotion. The only other known instance of such a promotion is Arima's promotion after defeating the Owl as a teenager.
- In Tokyo Ghoul Trump, Mutsuki is the "Three of Spades."
- To Dr. Shiba: "I'm hopeless... Ugh... Seeing blood makes me..."
- To Haise about Donato: "Sasaki... why does the CCG let someone like that live? When I look into that ghoul's eyes... it sends shivers down my spine."
- To unnamed CCG officials: "I don't really know why, but for a long time now I've only had unpleasant feelings about living as a woman. I want to live as a man from here on out."
- Internally: "For me... it's not a fact that I 'have' the [heart of a man]. But... I hate them. Men's eyes are so disgusting.
- To himself about his life: "If I could have run away to the sky, or to the sea, I'd have gone in a heartbeat. I guess this is my destiny. Always stolen away by men. Completely helpless..."
- About Sasaki: "Thinking of their face, whispering 'I love them' under your breath, feeling, in the depths of your chest, a warmth, and yet a tightness... That's what love is, isn't it?"
- To Kaneki: "Sensei, you've become very strange. Come back. I will remove everything that stands in your way."
- To Kaneki: "After them! Don't go. Please. I'll fucking kill you! I will! Sensei..."
- To Urie: "Did any of us... ever get the chance to taste such happiness?
- To Urie: "Why? Because I love him. I love inspector Sasaki. And there's nothing I can do about it. If there was, I'd do it. Come what may."
- To Urie and Saiko: "This is hopeless... It would've been better if I was dead. When I was taken by Torso, when I underwent the Quinx surgery, when I grasped the knife, when I was born into that house... I should have just died. But, then... living at the Chateau helped stitch me back together. I wanted to bring things back to the way they were before... he wouldn't even had to look back at me. I just... I just... It doesn't matter anymore... I don't want to hurt anyone more than the two of you. I can't keep deluding myself any longer. I was a human who should've died. I'm sorry for all of this."