Tooru Mutsuki

Tooru Mutsuki (六月 透, Mutsuki Tōru) is a Rank 1 Ghoul Investigator, an Quinx and a member of the Quinx Squad.

He is nicknamed "Eyepatch" by Dr. Shiba and the Hirako Squad.

Gender Identity
The revelations of Chapter 5 leave numerous unanswered questions concerning Tooru Mutsuki. It is revealed that he was born and was raised as a girl, and his official profile refers to him as female. However, a flashback reveals that he experienced feelings of discomfort related to living as a woman and could not explain the reasons behind these feelings. As such, when taken in by CCG, he requested to live as a man. Since then, he has lived with a fully male identity -- wearing men's clothing, using the men's restrooms, and being referred to using masculine pronouns. It is speculated but unconfirmed that Mutsuki is either a Transgender man or a woman passing as a man. As such, currently Mutsuki's true gender is unknown. However, masculine pronouns are used in the article in accordance with their use in the original text.

Appearance
Tooru is a slim, dark-skinned young adult with a dark green hair. He has green eyes, though his right eye is a permanently-active Kakugan with a dark grey sclera. As a result, he wears a medical eyepatch to cover it. After Sasaki gives him a leather eyepatch as a Christmas present, Mutsuki starts to wear that instead of the medical eyepatch. Similar to most of the other Ghoul Investigators, Tooru usually wears his CCG uniform consisting of the formal suit and tie, along with a short, white trench coat. Underneath his clothing, he has a large scar across his upper left pectoral and another across his right side. He also wears a small binder, flattening his chest and held in place with a pair of clips.

He initially wears his hair in a bob hairstyle, but after being promoted, he chops it off into a short style.

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.

Personality
Tooru is kind with a gentle heart and seems to be shy with little self-confidence. Having a constant case of Anemia, ironically, Mutsuki feels repulsive when he comes into contact with blood. Because of this anxiety, he faces discouragement as a ghoul investigator, to the point where he feels as though he isn’t even needed for the job. He expresses frustration with his own weakness, feeling anger at his lack of ability compared to his comrades. When not working, he is shown to enjoy reading books and is the one often left to relate information to Haise Sasaki. As such, he is shown to be a reliable and hard-working individual, 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.

A flashback reveals him to have been born female, but unable to reconcile his feelings of discomfort towards his birth sex. As such, he has 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.

Background
Tooru Mutsuki grew up in an ordinary family, with an older brother. When he was in Junior High, his family was killed in a Ghoul attack and he was left in the care of the CCG -- like most orphans whose families were slain by ghouls, he was sent to the Junior Academy to be raised as an Investigator. Though born as a female, he admitted to the officials that he had never felt comfortable as such and made the request that he be allowed to live and be referred to as a man. Following this, he adopted his current identity and spent the next several years under the organization's care.

His time at the Junior Academy was not a happy one, however. He was bullied by his peers, who called him names and spread rumors about him killing cats or even his own family.

Torso Investigation
Mutsuki is first glimpsed studying, and expresses confusion over the work. He resolves to ask his teacher, Sasaki about it the next day.

He is next seen visiting Dr. Shiba to have his blood drawn, as he has been suffering from a bout of anemia. He admits to feeling unfit as an Investigator, but hopes to at least be useful to his comrades. The doctor and patient briefly discuss his teammates, who he feels simply do whatever they want without regards to others. As he departs the office, he runs into members of Take Hirako's team and is intimidated into apologizing to them before rushing off. The other Investigators briefly discuss him, expressing negative opinions of the Quinx Squad.

Later that day, he meets with Sasaki to report the outcome of his recent investigation with Saiko Yonebayashi. A woman had heard growls in her neighborhood and feared that it would be a Ghoul, but Mutsuki reports that it turned out to be a stray dog. He then reports 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 locate and speak to Shimoguchi, requesting that he shares information on the Torso case. The other Investigator refuses and humiliates Sasaki in front of his subordinate, though Mutsuki is quick to reassure his mentor that he "looked cool". They are later able to track down Urie's whereabouts, arriving just in time to assist in the capture of a Ghoul. However, an argument breaks out between Sasaki and Urie, and the team again split up.

In a meeting with Dr. Shiba, Sasaki discusses the results of Mutsuki's latest tests. His RC levels are found to just barely be above those of a human, and he is noted to be unable to control his Kakugan. As a result, they worry that he won't be useful for the primary purpose of the quinx project.

That evening, Mutsuki greets Sasaki when he returns to the team's shared home and relays the whereabouts of the other members. Sasaki cooks dinner for him, expressing concern on his poor health and watching as Mutsuki eats the meal alone.

Akira Mado's declaration that her team will discover Torso's identity in a single month places greater pressure on the squad, leading to further tension among their ranks. While Urie and Shirazu investigate on their own, Mutsuki is recruited to help Sasaki in his own investigation -- he expresses concern that the other has lost it, when he declares he will show them all. The next morning, the pair head to Cochlea in order to speak to Donato Porpora and gain his assistance in the case. The Ghoul briefly turns his attention to Mutsuki, threatening and frightening him as he graphically describes his desire to eat the young man. After they depart the prison, Mutsuki wonders why such a dangerous Ghoul has been allowed to live and mentions the horrible look in his eyes.

Based upon the information provided by Donato, Mutsuki and his superior spend the following weeks gathering information about the previous victims. From interviewing people that knew the victims, they realize that Torso has been targeting women that have surgical scars and connect his hunting grounds to several hospitals. With time running out, they make the decision to split up and canvas the hospitals at the center of Torso's territory. On the 25th day of the investigation, Mutsuki visits a plastic surgery clinic and witnesses a taxi driver watching a woman with a predatory look. Though ordered not to do anything alone, he rushes over to the taxi and cuts in front of the woman. He feels a growing sense of unease, but attempts to make small talk with the driver. However, the driver suddenly turns on him and reveals himself to be a Ghoul, attacking Mutsuki while demanding to know "which" he is. The driver climbs into the backseat, and tears open Mutsuki's shirt to reveal his bound breasts.

Torso is excited as he finds out that Mutsuki is genetically a woman, and becomes excited upon seeing the scars on his chest. He manages to get his Quinque out and briefly fights back, but is overpowered and given a serious beating. Before Torso can do more, he notices Urie and Shirazu approaching the taxi on a motorcycle -- he takes off with an injured Mutsuki in the backseat, prompting a chase. Assistance from police units finally puts the chase to an end, and his teammates begin to fight Torso as Mutsuki climbs out of the taxi. He struggles to unleash his kagune, but is unable to do so and becomes frustrated at his weakness compared to the others. During the Quinx Squad's battle with Serpent, Mutsuki notes that they are no match for him, and therefore advises Urie and Shirazu to retreat. After Serpent escaped and Haise was shot down by Akira, Tooru stood by as he watched Haise received Rc suppressants.

Nutcracker Investigation
In the Quinx's living quarters, Mutsuki grew furious when Urie insulted Sasaki by calling him a "ghoul." Later on, Tooru advised Shirazu to apologize to Urie for attacking him.

Mutsuki is then seen alongside Shirazu and Sasaki discussing their new target Nutcracker. Tooru then informs Shirazu that Saiko would be back at nine o' clock that night. Upon entering the cafe "re," Mutsuki becomes puzzled at the fact that Sasaki uses the term "Kagune Nose" to represent his capability of smelling the coffee which the cafe made.

After the group leave the cafe to go home, Shirazu expresses concern over their mentor's odd behavior. Mutsuki agrees and clenches his hands in his trench coat anxiously, but drops the subject. Back at home, they find that Urie has returned and head upsets to confront Saiko. While the other two break down the door and berate her for neglecting her duties, Mutsuki fruitlessly attempts to repair the broken door.

The next morning, the team prepares to head to the 13th Ward to meet with Juuzou Suzuya and his team. While Shirazu tries to wake up Saiko, Mutsuki waits with Sasaki in the car. He begins to ask him something, but decides against it. During the meeting, he continues to give his mentor concerned looks as the events the previous day are recalled.

While they wait for their orders, Mutsuki and Shirazu comment about their waitress being very cute. Shirazu agrees with him, prompting him to tease him over having a crush on Akira. When their coffee arrives, he compliments the delicious taste happily. As they drink their coffee, Sasaki begins to cry, confusing both of his subordinates and leading to them to worry about his odd behavior.

After leaving the cafe, Mutsuki wonders what could possibly have Haise spacing out all the time. At the Quinx living quarters, Tooru informs the squad of Saiko's arrival, and is later surprised when Urie encouraged Saiko to start doing her work. The following day, Mutsuki accompanies Urie and Sasaki to visit the Suzuya Squad concerning the Nutcracker Investigation, where he once again notices Sasaki being inattentive to the discussion.

When he expresses confusion over Juuzou's arrival and unusual method of greeting Sasaki, Hanbee Abara explains the history between the two leaders. Shirazu finally arrives to the meeting, and surprises everyone by carrying a still-sleeping Saiko on his back. Mutsuki praises him for actually managing to bring Saiko to the CCG.

The Quinx Squad begin their investigation into Nutcracker by observing her at a local cafe, attempting to use their heightened senses to spy on her conversation. When Saiko won't take the mission seriously, he plays referee between her and a highly-annoyed Shirazu. Unfortunately, Shirazu knocks over a glass and draws attention to himself, causing their target to leave earlier than expected.

Later that evening, he listens to Shirazu's concerns about being a poor leader. Mutsuki reassures him that he's doing well, and reveals that Urie lied to Saiko about the details of their contract. He suggests they keep this to themselves for now, and puzzles over Sasaki allowing Saiko to neglect her work all the time.

The investigation uncovers an upcoming Auction, and the team decide to use the "ingredient" list in order to get closer to Nutcracker. For this purpose, Sasaki orders the team to go undercover at a nightclub, disguised as a group of young women. Mutsuki is extremely uncomfortable with this turn of events, and is overcome with anxiety at the thought of strange men staring at him. He ends up accepting a drink from a waiter, and quickly becomes intoxicated. This loss of inhibitions leads him to approach Nutcracker directly, complimenting her hair and chatting with her until she offers him a part-time job -- actually the trick being used to lure victims to the auction.

Having completed their mission objective, he rushes back to the others to report it. Sasaki attempts to berate him over drinking, but he ignores this and announces his intention to celebrate by dancing. Shirazu and Saiko join him, while Sasaki watches them from a distance.

With the time and location for the Auction obtained, Matsuri Washuu meets with Sasaki and Suzuya to discuss the operation. He decides to use Mutsuki as bait for the operation, ordering Sasaki to send him in undercover and alone. Suzuya intervenes, offering to accompany him undercover so that there will be a second person inside during the operation. Sasaki is relieved and entrusts Mutsuki's safety to Suzuya.

Later that night, Sasaki struggles to maintain his composure while informing Mutsuki of his role in the operation.

Mutsuki is seen being trained by Sasaki along with his teammates. Sasaki was disappointed with the results of their attack against him as they were armed while he was not.



Auction
A week prior to the Auction, Mutsuki meets with Suzuya to prepare for their infiltration. To train him, Suzuya demonstrates how to juggle knives while attacking at the same time, something Mutsuki does not feel he could ever accomplish. He wonders whether Suzuya is ever afraid of being injured by his knives, and admits to being afraid after seeing Sasaki lose control of his powers. He clarifies that he does not actually fear his mentor, but rather fears suffering the same fate. Suzuya advises him that fear can be a good or bad thing, depending on his ability to overcome his own weaknesses. Mutsuki takes these words to heart.

On the day of the Auction, many Investigators gather in preparation for the operation. Mutsuki, again disguised in women's clothing, is joined by a similarly-disguised Suzuya. The Quinx see him off, and the pair meet with Nutcracker to head to the auction site.

Some time later, Mutsuki awakens confused and disoriented. He drifts in and out of consciousness, but recalls that some sort of gas was leaked into the vehicle during their trip. Once he fully recovers, he attempts to contact CCG with a small device but cannot reach anyone. He realizes that he might be out of range, and has no idea whether anyone knows his location.

Eventually, Nutcracker comes to fetch him and roughly throws him onto stage. The Auctioneer, Uta, announces that this is a last-minute addition and the asking price would normally be 1 million -- however, this is not the case. A spotlight is focused on Mutsuki as he struggles to regain his bearings.

Realizing that he has become merchandise for the Auction, Mutsuki's thoughts begin to race. Uta makes a show of getting into his personal space, and notes his unusual scent before stealing his eyepatch -- exposing his active Kakugan to a shocked audience. Mutsuki cowers and tries to hide his eye, but the shock of a rare One-Eyed Ghoul being offered for sale sends the crowd of Ghouls into a frenzy of excitement. The starting price is set at Ten Million, but rapidly climbs as Mutsuki quickly begins to panic. His thoughts become a chaotic mess, alternating between thoughts of fighting and wanting to be saved.

Just then, Uta touches him on the shoulder and whispers something to him. Mutsuki falls silent, and meekly sits until the fierce bidding war between Kanae von Rosewald and Big Madam concludes in the Madam's victory. He is sold for a record 200 Million Yen, and escorted away by Nutcracker. The Ghoul is so delighted over how valuable he turned out to be, that she gives him a celebratory kiss on the check. As the operation begins, it is noted that Mutsuki has failed to contact them, leading to speculation that his transmitter was broken. With the auction house in chaos, Nutcracker attempts to make off with her "200 million", drawing the attention of Karao in the process. However, Mutsuki manages to kick his captor down and escape, taking refuge in a supply closet to gather his thoughts. He thinks 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 tries to make sense of this, realizing that someone knew about the operation but apparently allowed it to happen anyway. But before he can think about this further, he is greeted by Kanae -- who has decided to steal the "prize" for his master.

Cornered, he recognizes the Ghoul as one of the people involved in the bidding war. Kanae decides that he needs to confirm Mutsuki's taste, striking him hard enough to draw blood and licking the drops from his hands. Just like Kaneki, the taste of his blood proves to be incredible, bringing Kanae to tears at having finally found the unique flavor for his master. But before he can attack Mutsuki again, Saeki arrives and begins beating him. Frightened by the violence and recognizing him as Torso, Mutsuki tries to flee the room -- a desperate, wounded Kanae impales him through the stomach with his kagune to keep him from escaping.

Some time later, Mutsuki stumbles down a hallway while bleeding profusely. He wonders whether his wounds will even heal, and recalls how he was bullied at the Junior Academy in the past. Concluding that his life has been miserable, he thinks about meeting his family again. His wanderings eventually lead him into a hallway filled with the bodies of dead Investigators.



The next time Mutsuki appears, he seems to have somewhat recovered from his injuries. Kanae manages to locate him, and launches an attack with his kagune.....but Sasaki manages to pull Mutsuki to safety at the last second, while Urie and Shirazu fight. After Kanae and Matsumae retreat, the team reports back to command and learn that Nutcracker has eliminated the Ooshiba Squad. Sasaki requests that Mutsuki be allowed to retreat and receive medical treatment for his injuries, since they prohibit him from fighting against an S-rated Ghoul. Matsuri agrees to this, and orders Urie to handle the escort -- something that Urie initially fights against. Sasaki praises Mutsuki for his hard work, and entrusts him to Urie's care. As the pair retreat, Mutsuki inquires about Urie's isolation from the rest of the team and suggests that he is someone that others would like to be able to rely upon. Urie brushes these statements off, and claims to have gotten lost. Under this ruse, he instead goes to investigate the main hall and discovers a secret passage. Down below, they discover the Auction guests hiding place and are quickly joined by Juuzou Suzuya. Urie again lies, claiming to be unable to contact anyone and suggests that they attack.

While Juuzou and Urie fight down below, Mutsuki provides support from above. He manages to fend off and kill two members of Aogiri, before using his vantage point on the catwalk to locate Big Madam. He shouts this information to Urie, who goes charging off alone. By the time Mutsuki is able to catch up to him, Urie has already been defeated and is being swallowed whole by Big Madam.

Mutsuki rushes to try to help, but comes under attack by Madam's bodyguards. He's unable to fend them off, and collapses from several knife wounds while Urie goes berserk and frees himself. Completely out of control, the other Quinx kills the bodyguards and attacks Big Madam again, but is defeated and collapses to the ground while ranting about his hatred of the other Quinx. Mutsuki moves towards him, and is impaled through the stomach by Urie before he comes back to his senses. Though injured, Mutsuki brings out his kagune for the first time and offers words of comfort to the other. He realizes the scent of blood is from menstruation rather than an injury, expressing confusion over this while Mutsuki remains silent. The pair are interrupted by Big Madam, who prepares to attack them. Juuzou and his squad arrive, and surround Mutsuki and Urie in preparation to fight the Ghoul.

After back up from CCG begins to arrive, Mutsuki is seen quietly sitting besides Urie with his head looking downwards.

Post Auction
A month has passed since the Auction mopping-up operation and Mutsuki is helping Sasaki prepare for a Christmas party. He takes inventory of the pantry and asks Urie to do the grocery shopping. He refuses, but then reluctantly agrees due to Mutsuki's insistence. That night at the party, he receives a leather eye-patch as a gift from Sasaki.

Rosewald Investigation
Spring has arrived and it's time for the CCG's award ceremony. Mutsuki has been 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 wonders to himself if he's worthy of the position. Iwao Kuroiwa also makes an appearance at the party and Mutsuki is in awe about how he can still continue as an investigator even though he lost an arm.

Some time later, Matsuri holds a meeting about evidence found after the Auction that suggests that the Rosewald family is still around and may be responsible for the kidnappings. The evidence is based on Kagune markings left on Quinque and how they have certain similarities. After the meeting, Mutsuki asks Sasaki about Kagune matching among relatives.

When visiting HySy ArtMask Studio along with the rest of his squad to get mask measurements, he finds Uta's voice to sound familiar, but he fails to remember where he heard the voice from.

Mutsuki is among the Investigators observed by Shuu Tsukiyama, constantly interrupting his attempts to speak privately with Sasaki. To this end, Kanae hires several members of Aogiri to eliminate Mutsuki and his comrades.

The Quinx enter a parking garage to investigate, and are ambushed by Kanae. While Urie and Shirazu are lured away, the others are attacked by a group of Ghouls led by Hooguro and Shousei. Sasaki orders Mutsuki and Saiko to find the others, realizing they have fallen into a trap. As Mutsuki attempts to catch up with the others, Torso appears before him and begins attempting to flirt. In response, Mutsuki orders Saiko to escape and begins attacking the Ghoul -- displaying a significant increase in his strength and fighting prowess. Torso is thrilled by this change, even as Mutsuki continues to attack him.



Grave Robber intervenes, blocking Mutsuki's strikes with a quinque sword. The two fight each other, proving evenly matched and blocking each others' strikes. Mutsuki unleashes his kagune in an attempt to overwhelm his opponent, disarming the Ghoul and moving in the for kill. However, Grave Robber expresses amusement at facing another Bikaku and uses their own kagune to drive Mutsuki back. They retrieve their quinque and Mutsuki braces for the finishing blow, but is rescued by Urie. Faced with three Quinx, the Ghoul retreats and Mutsuki leads the others back to Sasaki. They are shocked to see him fighting with both quinque and kagune, slaughtering his opponents effortlessly. As the survivors are driven off, the squad hurries outside to help Saiko and find her alone in the alleyway.

One day after Shirazu decides to cut all of his hair Mutsuki asks with some worry as to who cut it. Later on, he's present during the meeting on how to deal with the Rosewalds where he sits next to Saiko and tries to keep her awake. He quietly listens as Sasaki requests that he and his squad take advantage of their half-ghoul sides in order to gather intel from the ghoul world.

Mutsuki is seen on a rooftop wearing his ghoul mask along with the Quinx squad overlooking the city and looks uncomfortably at Sasaki's mask. He was paired up with Urie and they tried to get information with the ghouls who avoided them. When Sasaki asks if they let a ghoul escape, Mutuski answers quietly they did and looks surprised by Saiko's comment that some ghouls were good. Shirazu asks Sasaki how he was doing and as their mentor cheerfully laughs that he wasn't doing well Mutuski looks confused at his answer.

Haise Sasaki
Mutsuki looks up to Haise 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 Haise. 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. Tooru 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 Haise. Tooru admitted that he is afraid after seeing Haise losing control; it's not that he fears his superior but rather it's a fear of losing control the same way.

Kuki Urie
Mutsuki and Urie are 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 Haise; 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.

Ginshi Shirazu
They have a close friendship, frequently joking around and spending their free time together. Mutsuki's more gentle and observant personality works well with Shirazu's more aggressive nature, making them good friends that are able to balance each other out. He frequently acts as a mediator between Shirazu and the others when he loses his temper, helping to smooth out disagreements before they can cause problems within the team. He also serves as Shirazu's primary confidante after being promoted to Squad Leader, listening to his worries and offering reassurances or advice. Shirazu shows a protective streak towards him, while Mutsuki compares himself negatively to his stronger comrade in terms of fighting ability and powers.

Saiko Yonebayashi
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. According to an omake, he spies on Saiko's twitter account to find out when she's ditching work and is often the one to pass news about her to others.

Karao Saeki
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 expresses distress at his own weakness, having to be rescued by his comrades and unable to help them fight. Since their encounter, Torso has become obsessed with him and shifts from hysteria to extreme violence when Mutsuki is in danger.

Powers and Abilities
Like all members of the Quinx Squad, Mutsuki has received preliminary training in combat and investigative procedures. His body has been 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 was he able to wield his quinque well. He does, however, show a decent level of regeneration. A short time after being stabbed through his arms by a kagune, he is shown using them without significant impairment. He is also shown to have exceptional eyesight, able to make out details from long distances even with one eye normally covered.

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 has learned to control his kagune and improved on his dagger wielding after being taught by Juuzou. He's improved so much that Sasaki, who at first was concerned that Mutsuki wasn't 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.


 * Bikaku Kagune: His Kagune possesses several segmented edges. Hes able to extend it too a long distances and use it to block, make rather powerful attacks, or to bind an enemy.

Trivia

 * Mutsuki has numerous traits in common with Kaneki at the beginning of the original series, including his meek personality and difficulty controlling his powers.
 * Others refer to him as "Eyepatch-kun", the alias once given to Kaneki.
 * His kakugan is permanently activated.
 * Mutsuki has a RC level of 655, which is the lowest compared to the other members of Quinx Squad.
 * He dislikes rare cooked meat.
 * In contrast to his gentle personality, Mutsuki uses the personal pronoun "Ore", usually reserved for male characters that are tough or aggressive.
 * 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 is associated with the Tarot cards The Wheel of Fortune, The Chariot, and Death.
 * Mutsuki was rumored at the academy to have killed a cat, something people said Juuzou had done as well (although he did not kill the cat, he never argued otherwise).
 * For his contribution to the Auction mopping-up operation, Mutsuki is awarded a two-rank Promotion. The only other time such a promotion has occurred within the series was Arima's promotion after defeating the Owl as a teenager.
 * In Tokyo Ghoul Trump, Mutsuki is the "Three of Spades". (This represents the Three of Swords from the Minor Arcana.)

Quotes

 * To Dr. Shiba: "I'm hopeless...ugh. Seeing blood makes me..."
 * 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."