Ken Kaneki

Ken Kaneki (金木 研, Kaneki Ken) is the protagonist of the story. He used to be a normal human living a normal student life, but due to certain events, he earns the transplant of Rize's kakuhou and became a One-Eyed Ghoul. Kaneki starts struggling with hardships one after another, between being a university freshman studying Japanese Literature at the Department of Literature of Kamii University and being a part-time waiter working at Anteiku, where he becomes known as Eyepatch (眼帯). Currently, he leads his own group of ghouls under the goal of protecting the ones precious to him and the goal of "picking out" the people who threaten the place he belongs to. While active with his group and searching for answers, he had been seen using his second kagune, which has given him a nickname in accordance to its resemblance as Centipede (百足).

Appearance
As a child, Kaneki had all the same features he has now as an adult. As a normal university student, Kaneki is a scrawny young man with little to no athletic background who prefers to read books. In his free time, he wears casual clothes. At work, he wears the regular Anteiku waiter uniform, consisting of black trousers and a black waistcoat over a white dress shirt and a black necktie. Because he can't properly control his one kakugan that manifests in his left eye, he wears a medical eyepatch to cover it. His ghoul mask shows resemblance to a leather gimp mask with an eyepatch and lipless grin that shows artificial teeth, much like a restrained asylum monster. The bolts sticking out of his neck and the fact that he is an artificial ghoul, gives him a Frankenstein theme.

After being tortured by Yamori for a period of ten days, his hair became white and his nails turned black because of heavy, mental stress, anxiety and continuous regeneration.

During his fight with Kishou Arima, he lost his left eye (Kakugan), and then his right eye.

Personality
Kaneki is a shy and reserved person with Hide being his only close friend. He usually spends most of his time reading books, mostly novels. He is extremely gentle and appears to be optimistic most of the time. Influenced by his mother and a true testament of modesty, he willingly takes blame and punishment from others so that he can be someone who doesn't hurt people but rather "the person getting hurt". However, this lack of assertiveness normally gets him bullied and taken advantage of.

However, beneath his selfless and gentle nature is an underlying fear of being alone. Ever since his mother died, Kaneki has developed his personality to resemble his mother's. He despises the idea of solitude, hence he tries to protect those dear to him so he would not have to face his fears of being alone in the world.

This is perhaps his greatest weakness and act of selfishness. Since Kaneki is always trying to protect others, he is essentially trying to protect himself from becoming alone again. Therefore to escape that scenario, he would shoulder the task of protecting other onto himself without looking for others to help him. This is also the reason why Kaneki seems to reject the notion of "living" because to him, watching others die before him is the beginning of returning to those lonely days without anyone behind him.

After he was turned into a half-ghoul, he clings to his human side. To keep his life in the human world, he began to work at Anteiku and had built relationships with the ghouls there. Because of his experiences, he had started to have interest in becoming stronger and began reading martial art books so that he could protect himself and the people close to him. He was troubled with the fact that he is a half-ghoul and is searching for a place he can belong to. If people close to him are threatened, Kaneki will try to protect them even he is the one who gets hurt the most instead.

After his time being held captive during the Aogiri arc and undergoing constant torture by the hands of Yamori, Kaneki's personality changes. He becomes more ruthless and brutal in order to protect his friends, all the while maintaining complete composure. He no longer fears his ghoul side and as a result, he becomes much more cold and barbaric during battles such as when he began eating Yamori's kagune in order to strengthen himself. By embracing his ghoul nature wholeheartedly, Kaneki has given up being "human".

While still capable of showing his previous gentle nature to those he cares about, he can automatically turn merciless with a blink of an eye against his enemies or those he does not trust, such as Tsukiyama. Banjou hypothesized that Kaneki has developed some form of mental instability during his time in the 11th ward and that this would gradually wear him down.

After raiding Kanou's lab and attacking Banjou, Kaneki begins to revert back to his old personality from before the Aogiri Arc. However he enters a period of soul-searching, seeking to reclaim his human side as well as becoming uncertain about the path he has taken to become stronger. He also starts to really question and seek answers from individuals such as Uta, Yomo, and Yoshimura in order to understand the incidents that have happened around him since he turned into a ghoul.

Whenever he is near-starvation or loses control of his kagune, he seems to develop a personality that emulates Rize.

Etymology
Kaneki (金木) means "Gold Tree". Ken (研) means "Research" or "Laboratory".

Background
Kaneki liked eating the burgers that his mother made when she was still alive.

He lost his father when he was four years old. He barely remembered his face and was awfully curious as to what sort of person he was. He knew that his father was an avid reader and had loads of books. As Kaneki followed the sentences in the books his father had been reading, he felt like he was having a conversation with his father which calmed him down.

His mother later died overworking herself when he was ten. All the work that she had to deal with was too overwhelming and the one who put the most stress on her was Kaneki's aunt (his mother's sister). His aunt was tight on money and hounded his mother for cash. Being left with nothing but burden, his aunt can be seen as the one who drove his mother to her death. He was then adopted by his aunt's family, the Asaoka family, after his mother passed away.

His aunt's son, Yuuichi, who she always compared with him since Yuuichi did not do well at school. This greatly angered her. When comparing her son with Kaneki, she also compared Kaneki with his late mother, saying how alike they were. Her feelings of inferiority regarding Kaneki's mother were turned on him as spite. As time passed, the family became a place that did not give Kaneki any comfort for long because nobody in the family would look after or care for him.

He barely had any friends during elementary school. During that time, Hide approached Kaneki, most likely because he noticed that Kaneki had trouble dealing with his classmates. Since then, Hide and Kaneki have been best friends. Hide was his only support during the time the Asaokas began to ostracize him, which really saved him from loneliness.

Prologue
In the first chapter, Kaneki and Hide listened to the news about ghoul attacks in the 20th ward while in Anteiku. Hide wondered if Touka was Kaneki's new crush that he wanted to show him, but Kaneki denied it. Instead, He pointed to Rize as she entered the café. After Hide had left the place, Kaneki ended up being arranged to a date with Rize. However, Rize turned out to be a ghoul targeting Kaneki, which she revealed after tricking Kaneki into entering a quiet alley. During her attack, Kaneki was wounded in the abdomen by her kagune, but steel bars fell on her and apparently killed her before she could kill him. To save his life, the staff of the Kanou General Hospital under the direction of Dr. Kanou decided to transplant Rize's organs into him. From then on, Kaneki became a half-human, half-ghoul.

After the accident, Kaneki hid the fact that Rize was a ghoul. He found everything he ate tasted disgusting and he was hardly able to eat normal food, so he started to live only on water for days. Around that time he realized that ghouls were also unable to eat normal food, his hunger struck him. Unable to find anything to satisfy his hunger, he wandered the streets. At that time, he found out that the waitress, Touka, from Anteiku was also a ghoul when she killed a human in front of him. In terror, he ran away. He soon saw that he could barely keep himself in check. Since he thought the organ transplant was the reason for his transformation, he tried to get rid of the transplanted organs, but was unsuccessful. Desperate, he turned to Touka for help. Touka refused to give assistance, but Anteiku's manager Yoshimura kindly gave Kaneki human meat to satisfy his hunger.

However, Kaneki was still repelled by the thought of having to eat human meat, so he decided to continue rejecting it. Instead, he looked for other digestible food frantically. He discovered that he was still able to drink coffee. Drinking coffee calmed him down, so he went off to buy more. In a store, a man revealed to be Nishio advised him to buy the instant coffee "Blondy". As Kaneki was returning home, he noticed the smell of delicious food. He traced the smell's source, which turned out to be a human corpse. The ghoul Kazuo Yoshida was eating the freshly slain body, but he was immediately killed by Nishio. Asserting that this was his feeding ground, Nishio attacked Kaneki too. At that moment, Touka appeared and declared that this place wasn't Nishio's feeding ground, but Rize's. Nishio retorted that this was originally his feeding ground until Rize came, but Touka, unfazed, responded that the feeding grounds would be re-alloted among the weaker ghouls and that it was his own fault for being too weak. Angered, Nishio attacked Touka, but was immediately defeated. Touka tried to force Kaneki to eat some of the meat, but Kaneki hysterically screamed that he was human and different from ghouls. Angered, Touka retorted that Kaneki was neither human nor ghoul and no place where he belonged, but she also warned him that a ghoul's hunger was hell.

When Kaneki and Hide visited a senpai from the university to get the DVD of the previous year's college festival, they disturbed him and Kimi when they were making out. Kaneki realized that the senpai was Nishio, the ghoul that attacked him shortly before. Nishio told them to help him look for the material, but then claimed that he took the disk home. He proposed that they should go to his home. In reality, he deceived Kaneki and Hide, knocked Hide out and started fighting Kaneki. He provoked Kaneki by puking on Hide than standing his face with his foot, but angered Kaneki was no match for Kagune-wielding Nishio. However, when Nishio tried to kill Hide, Kaneki made his kagune come out. With his kagune, Kaneki heavily injured Nishio. As Kaneki started to lose control and was about to eat Hide, Touka stopped him.

Later, Kaneki woke up and found himself inside Anteiku. The manager led him to the sleeping Hide. Kaneki wanted to approach Hide, but stopped. Before, he had already noticed blood inside his mouth and his diminished hunger, so he asked Yoshimura what he had eaten. The manager told him that he already knew what the answer was, since there is only one way to satisfy a ghoul's hunger. Kaneki cried out that he was neither human nor ghoul and there was no place for him, but Yoshimura replied that he was wrong and that he belonged to both worlds. Yoshimura proposed that Kaneki to work at Anteiku. Yoshimura would teach him how to live as a ghoul so that Kaneki could keep his place as a human.

Doves' Emergence
After Kaneki had started working part-time at Anteiku, his friend Hide visited him there. Hide thanked Touka for nursing Kaneki and him after the "car accident", the lie the manager used to cover up what had really happened to Kaneki and Rize. After they had left Hide, Touka told Kaneki to make sure that Hide won't find out about him being a ghoul: she would kill him to protect the ghouls' identities if that were to happen. Afterwards, the manager showed Kaneki how to eat sandwiches like a human. After Kaneki gave it a try, the manager gave him special sugar cubes that he could use to curb his hunger, but warned him that he might have to eat meat when the time would come. During Kaneki's working time, Ryouko Fueguchi and her daughter Hinami came to Anteiku. Touka told Kaneki that these two ghouls did not hunt themselves.

Ghoul investigators from CCG entered the 20th ward looking for Ryouko Fueguchi and her daughter Hinami. As the news spread in the ward, the manager asked Touka to guide Kaneki to the mask shop HySy ArtMask Studio in the 4th ward, where Kaneki became acquainted with its owner, Uta.

One day, the manager asked Kaneki to obtain "food supplies" with Yomo, i.e., they looked for humans who committed suicide. Afterwards, they picked Ryouko up, who was warned by Yomo that the investigators came because of her and that she should move more prudently for Hinami's sake. Ryouko agreed and said she would stop relying on her dead husband so that Hinami could depend on her. Kaneki thought that a parent's concern for their child was strong in any world.

Few days later, while Hinami was eating human meat in a room on Anteiku's second floor, Kaneki suddenly entered the room without knocking on the door. After he apologized, she asked if he is ghoul or human. To answer her question, Kaneki explained his situation. He noticed that she had one of Takatsuki's books, so they started to talk about the stories. Kaneki also tutored Hinami how to read some new kanji to expand her vocabulary. Before she and her mother left, Hinami thanked him and asked him to teach her again next time. When she and her mother left, the ghoul investigators encircled them. Ryouko gave her daughter the chance to escape while she fought the investigators. During her escape, Hinami ran into Kaneki and asked for help, but just as they arrived, Mado killed Ryouko. Kaneki participated in Anteiku's meeting after Ryouko's death. Kaneki considered Ryouko's death his fault for being too weak to save her.

The next day after Touka's attack on the ghoul investigators, Kaneki noticed Touka's injuries. He intended to treat her wounds, but Yoshimura stopped him, because Touka would have to carry the responsibility for her actions herself and Anteiku didn't have the power to oppose CCG. Even so, Kaneki still chose to treat her wounds. Kaneki told Touka that he believed the ghoul investigators' existence was necessary and that he considered her actions wrong. Nevertheless, he would mourn her were she to die, and asked her to teach him how to fight, so that he would be able to act next time. The next day, they entered the underground, tunnels originally built by ghouls, to practice. By threatening his life, she forced him to use his kagune. After training, Uta delivered Kaneki's mask.

Later, they went to CCG's branch office in the 20th ward to spread false information on Hinami's whereabouts. Before they could leave, Mado suspected them to be ghouls, so he forced Kaneki through the Rc scan gate, but the gate didn't react to Kaneki. While Hinami confined herself in Anteiku's room on the upper floor, Touka visited her and gave her a newspaper that contained Kusaba's death notice. Realizing what Touka was doing, Hinami ran away. When Touka and Kaneki noticed Hinami was missing, they split up to search for her. Touka found Hinami and informed Kaneki, but before they could leave, Mado attacked them. Kaneki was relieved they had found her, however, he overheard investigator Amon's phone conversation with Mado. As Amon set off for Kasahara River where Hinami and Touka were, Kaneki, wearing his mask, stood in Amon's way to try to buy enough time for Touka and Hinami to flee.

Kaneki initially underestimated the investigator until Amon was easily able to overpower him. After taking down Kaneki, Amon paused to talk about the recent death of a fellow investigator, the orphans and demonized ghouls for corrupting the world with their gluttony. As a former human, Kaneki couldn't deny that ghouls had brought violence to the world and caused tragedies because of their consumption. However, after remembering Ryouko's sacrifice for her daughter, he finally realizes the truth to Yoshimura's earlier comment, that he is the only one who can see both the human and ghoul worlds in their entirety. That they could manage to get along due to their similarities if they would sit down and talk.

Convinced that he has a reason to fight, Kaneki won using his reluctantly-used kagune. After defeating Amon in battle with his ghoul instincts excited, Kaneki starts losing control of his powers. Desperately, he asked Amon to leave so that he didn't have to kill someone. Shortly thereafter, Kaneki lost control and he started acting like the binge-eating Rize. Yomo appeared and stopped Kaneki from rampaging. Yomo and Kaneki rushed to Hinami's and Touka's whereabouts and afterwards left to go back to Anteiku. On their way back, Hinami asked if it was right for her to live and Kaneki answered that he believed Hinami's mother told her to live in her last moments.

After Mado's death, Kaneki went to Kanou General Hospital for a checkup. Kaneki heavily questioned if Kanou knew what had happened to his body. Afterwards, Kaneki went to university. During class, Hide brought up the news about the death of two ghoul investigators. To Kaneki's concern, Hide had mostly figured out the Rabbit case through deduction. As Kaneki asked Hide why he was interested in this matter, Hide pulled out Hisashi Ogura's new ghoul book that he found really interesting. Hide toyed with the idea of joining the investigation to which Kaneki heavily objected.

Later on, Kaneki went to Touka's apartment because he was worried about Hinami who had started living there. To Kaneki's surprise, Touka ate all of the home-made food by her classmate Yoriko, making him wonder how important Yoriko was to Touka.

Gourmet Arc
The day after Touka and Kaneki practiced underground with Yomo, Tsukiyama, nicknamed the Gourmet, came to Anteiku during their work time and was attracted to Kaneki's smell. On a later date, Tsukiyama approached Kaneki in his university as Kaneki immersed himself in a martial arts book. Tsukiyama persuaded Kaneki to meet him at a cafe the next Sunday. Lost in thought, Kaneki went to Anteiku despite it being closed and met Yomo in front of Anteiku. Yomo invited Kaneki to meet someone who asked for Kaneki. Together, they went to 14th ward's Helter Skelter bar and met Yomo's old friends, the bar owner Itori and Uta. After they had talked about the relationship between Yomo, Uta and Itori, Itori spilled a glass of blood on Kaneki to uncover his sole kakugan. Itori was excited seeing a One-Eyed Ghoul and wondered if the other "One-Eye" felt as self-conscious about his eye as Kaneki. Kaneki wanted to know about the other one-eyed ghouls, so Itori told Kaneki about hybrids, pregnancy of half-ghouls and the rumored "One-Eye". Soon, the conversation turned about Kaneki and Rize's mysterious death, and Kaneki discovered that the accident was likely set up by someone. Itori proposed a trade to Kaneki: if Kaneki uncovered information on the Ghoul Restaurant from the Gourmet, namely Tsukiyama, she would share information on the accident.

After the meeting, Kaneki, immersed in thought, got lost and ran into a group of ghouls that were attacking Nishio. Kaneki saved Nishio from the ghouls that planned to eat him and returned him to his apartment, while Nishio was cursing him. As Kaneki was about to leave, Kimi attacked Kaneki to protect Nishio, thinking that Kaneki was the "narcissistic man"; however, Nishio asked her to stop.

The following Sunday, after Kaneki and Tsukiyama played Squash, they visited the café. A book page cut Kaneki's finger and he used Tsukiyama's handkerchief to soak up the blood. Tsukiyama went to the bathroom with the handkerchief and sniffed it, revealing his obsession with Kaneki's smell, flesh and blood. As Kaneki asked Tsukiyama about the ghoul restaurant to gather information, Tsukiyama invited him as a guest to the ghoul restaurant. However, this was a trap set by Tsukiyama, because he was not meant to be a regular guest, but instead was meant to become the dinner together with Kobachi and Ami. As Kaneki was fighting the restaurant's scrapper Taro-chan during the dismantling show, his one kakugan activated, revealing him to be one-eyed. Tsukiyama realized that Kaneki was an even rarer dish than he had thought and came to the conclusion that he didn't want to share with the other members, so he killed the scrapper as Kaneki's replacement.

Kaneki, frightened of Tsukiyama, slept at Anteiku for the night. The next day, Hinami, also bringing along the cockatiel Loser, Yomo, and Yoshimura, visited Kaneki. Kaneki told them he saw lots of ghouls and commented at how they laughed behind their masks as he, Kobachi, and Ami were injured. Yoshimura commented that they were ghouls who killed their emotions and forgot the value of life. After Yoshimura and Yomo left, Touka called Kaneki because a girl was waiting downstairs for him. Kimi begged Kaneki for help since Nishio's state had worsened further. Kaneki promised to help her. As she was returning home, Tsukiyama kidnapped her to set the next trap for Kaneki.

After Kaneki had found Tsukiyama's letter about Kimi being kidnapped by him, Nishio came looking for Kimi. Kaneki and Nishio decided to face Tsukiyama together to save Kimi. However, Kaneki and Nishio were no match for Tsukiyama, and even after Touka joined them, they were on the losing side because Tsukiyama was the only one who could use his kagune. However, Nishio's tenacity and Kaneki's idea to allow himself to be eaten by Touka led to victory against Tsukiyama.

Aogiri Arc
Banjou and his followers came to Anteiku to search for Rize by orders of Aogiri's leaders. Touka and Kaneki decided to hear his story, and Banjou began to talk about his time with Rize in the 11th ward. However, Banjou soon realized that Kaneki smelled like Rize. Because he suspected Kaneki to be her boyfriend, he attacked him, but Banjou was easily knocked out by Kaneki. When Banjou woke up again, Kaneki tried to clear up the misunderstanding. He told Banjou that Rize had moved somewhere else, hiding from him that she had died. Banjou asked Kaneki to tell her that she should run away because he feared that Aogiri would try to gravely hurt her. At that moment, Ayato Kirishima, Yamori and Nico raided Anteiku. They announced that they were ordered to capture Rize herself or "the person who smells like her". Touka and Kaneki were easily overpowered and Kaneki was kidnapped.

After Kaneki had regained consciousness, he asked Ayato about Touka's condition, but in response, Ayato taught Kaneki the rules of the place while kicking and beating him. Kaneki was brought before Tatara. To make Kaneki reveal his kakugan, Tatara pierced his abdomen. Tatara realized that he could not use Kaneki the way he originally planned, so he granted Ayato the right to do whatever he wished with Kaneki. Tatara revealed to Kaneki that the escaped Doctor Kanou was aware what had happened to Kaneki's body and that Kanou didn't transplant a kidney into Kaneki, but a Kakuhou.

After the meeting, Kaneki was approached by Banjou, who proposed that they should escape together.During the meeting, he meets Banjou's resistance group who were also subdued by Aogiri. Banjou proposed that because the Aogiri superiors take turns leaving on different days of the week, they will make their escape when security is light.

On the night of the escape, the Anti-Aogiri group attempted to escape. However, the Bin brothers were alarmed by their escape and went after the group to intervene. When Banjou stayed behind to cover their escape, Kaneki and the gas mask followers came to his aid to confront one of the Bin. Admist of fighting, Yamori and Nico joined them along with several of the resistance members, revealing that they have overheard their plan and proceeded to ambush them. Despite knowing that death is the penalty for betrayal, Yamori instead proposed to Kaneki that he will overlook this event in exchange for his cooperation as an assisant because he possessed Rize's organs and had 'potential.' Kaneki hesitantly accepted, knowing that they would be killed otherwise and was taken by Yamori and Nico into his "hobby room".

10 days before the CCG stormed the Aogiri hideout, Yamori showed Kaneki his "hobby room". Kaneki is shocked when he sees a dead person sitting on a chair, whom Yamori reveals to be his former underling who is tortured for making a mistake. Yamori showed Kaneki Rc suppressants and explained that they are are used to weaken ghouls and forcibly injected the drug by stabbing Kaneki's left eye with a syringe. After the injection, Kaneki's body was weakened so that Yamori could torture him for pleasure. Days of torment took a toll on his physical and mental state. Trivially, Yamori reveals to Kaneki that Kanou had known he was surgically making him into a half-ghoul and that Rize's kakuhou was "special" for it's abnormal vigor.The torment had made his hair whiten and he begins to wonder what has happened to his friends. In a state of despair, he begins to hallucinate Rize and began to reminisce over his tragic past. Rize called him and his mother weak, but Yamori appeared with Kei and Kouto before she finished. Enraged that Yamori didn't fulfill his end of their bargain, Kaneki was given another ultimatum: Who of the two will he spare? Unable to comply to Yamori's twisted pleasure, Kaneki refused as Nico protested against Yamori's distasteful violence. The aggrivated Yamori ultimately killed both the mother and child ghoul and he and Nico left Kaneki in despair. Rize's illusion spoke to Kaneki, taunting him that it was his weakness that lead the two to their grisly demise. 'Rize' reasons that if more brutal ghouls like Yamori and Aogiri were to come to power, then his friends will eventually suffer similar fates. Realizing that in order to prevent this, he must become a ghoul full-heartedly and learn to control his kagune.

During the CCG attack, Yamori returned to Kaneki. He told him of a rumor that if a ghoul were to cannibalize one another, they will become stronger but ghoul meat was considered disgustingly distasteful. When he motioned to carve out Kaneki in order to eat him, Kaneki bites him and agrees with his latest notion. Freeing himself from the chair, he attacks Yamori and bites him, jeering that ghouls were indeed made to compete and that it can't be help that Yamori could be devoured, too. The two fought with their kagunes, in which Kaneki eventually overpowers him and proceeded to eat Yamori's kagune. After feasting on his kagune, Kaneki reminded him, before leaving, that the CCG will come to the hobby room and kill him while he has been wounded and disarmed.

Kaneki later fights Ayato and "half-kills" him by breaking 103 out of 206 bones in Ayato's body as revenge for Touka.

Raid of Kanou's Lab
After the invasion of the Aogiri hideout, it is rumored that he was the one to single-handedly destroy the Ghoul Restaurant and kill about 50-60 members. In the Ghoul Restaurant Kaneki confronted Kuro and Shiro, two one-eyed ghouls with the same abilities from Rize, which were later confirmed to be newer products of Doctor Kanou.

Anteiku Raid
After overhearing CCG officers' plans to raid Anteiku, Kaneki decided to head there as fast as possible to help out Yoshimura. During his way in the 20th Ward, Amon appeared in his way and began fighting him with Kaneki retaliating unwillingly. With a new quinque, Amon held an advantage over Kaneki. However, Kaneki chose to activate his Kakuja and overwhelmed his opponent easily, even when Amon received a newer quinque made for him mid-battle. Slashing off Amon's left arm but losing a chunk of meat on his waist, Kaneki retreats into the sewer paths to continue on. In the sewers he gradually begins to lose his mind due to his incomplete-Kakuja's side effects until Hide appears. Trying to convince himself that Hide couldn't possibly be there and what he's seeing is in fact an illusion due to his madness, Hide confronts him and tells him he knew Kaneki became a ghoul but still wants to aid him. After being told that CCG has surrounded the entire place, Kaneki is asked by Hide if he can go all out once more to escape the raid.

Kaneki passes out and wakes up with a sweet taste in his mouth. Hide is nowhere to be found so he continues to wander around the sewer only to run into Kishou Arima in what he first believes to be a flower field, later found to be a field of Ghoul corpses slain by Arima. He instinctively knows who Arima is but is nonetheless drawn into a battle with him, getting pierced in the back and stabbed through his one kakugan eye. After he gets 8 claws on his kagune, he decides to finish Arima with one hit thinking that because Arima is a human he would die, but was instead blocked by Arima's quinque Ixa's, defensive barrier. Then Arima revealed that he knew who Kaneki was by calling him by his name and saying that he was impressed that Kaneki managed to damage his quinque. Arima then went on to pierce Kaneki through his body with Ixa which raised him from the ground before dropping him in front of the man. After stating how he hadn't expected Kaneki to damage his quinque, he stabs Ixa through his head before mentioning he needed a new quinque.

Hideyoshi Nagachika
Kaneki's best friend, who he calls by his nickname, Hide. The two of them are very close and have been close friends since childhood. Although Kaneki would lack the assertiveness to speak to others, Hide would often speak in his place as his "voice". Kaneki is willing to fight to the death for his friend, and Hide is able to perceive Kaneki's emotions. The strong connection between Kaneki and Hide earns Kaneki the capability to refrain from human meat even when driven by ghoul instincts. He cares for Kaneki immensely, and did not falter to help him even after finding out about Kaneki's transformation into a ghoul. It might be possible that Hide was eaten by Kaneki.

Touka Kirishima
Before discovering that she is a ghoul, Kaneki would see her as a cute girl. She was confused to see a half-ghoul and refused to show any compassion to him, as he is a former human. Ever since Kaneki joined Anteiku, the two of them became close, even though she would boss him around. Touka helps him many times because she really cares about him, even though she pretends it is only because he is a co-worker and it would increase her workload if something were to happen to him. Kaneki also started to care about her as much as he cares about Hide. They developed a similar taste in clothing. After training together their battle skills are synchronised. After Kaneki's ghoul 'awakening', Touka also showed some form of grief when Kaneki refused to go back to Anteiku.

Yoshimura
Kaneki is grateful for Yoshimura helping him survive being a ghoul. He would also listen to him with care to what he has to say. Since Kaneki is working part-time in his shop and would take missions from him, he is affiliated with Yoshimura's organization Anteiku.

Renji Yomo
Initially, Yomo is distant and uncaring towards him when Kaneki first cooperates with him in a body scavenging mission. Yomo is aware that he is half-ghoul and grew interested in his development after Kaneki's fight with the doves. Sometimes, he gives advice to Kaneki whether on fighting or avoiding trouble.

Enji Koma
Kaneki shares tied relationship with Koma under co-work bonds. Kaneki also feels most relaxed working with Koma than working with any other members from Anteiku.

Nishiki Nishio
At the beginning, Nishiki starts enmity toward Kaneki just because he thought that he Kaneki was invading his feeding ground, and as the way he shows his strength to weaker ghouls.

After many events and joining Anteiku, he became more like a close friend to Kaneki.

Hinami Fueguchi
Hinami looks up to Kaneki as a big brother. She's aware and interested in his half-human nature as she may had a few or no interaction with human society. They both share a passion for reading, especially Sen Takatsuki's works, and he often tutors her in new vocabulary to learn. After her mother's death, both Touka and Kaneki have been very protective of her and treat each other like family.

Alongside with Banjou and Tsukiyama, she joins Kaneki's group of ghouls.

Shuu Tsukiyama
Kaneki was one of Tsukiyama's victims who were deceived into visiting the Ghoul Restaurant. While Tsukiyama later decided to not share Kaneki's "rare meat" with anyone, being obsessed with Kaneki's flesh and blood.

After Kaneki got out from the Aogiri hideout, he accepts Tsukiyama to joining his group of ghouls so that he will get much help from him, even though he doesn't trust him. Despite this mistrust, Kaneki still retains a respectful relationship with Tsukiyama.

Kazuichi Banjou
Banjou considered Kaneki as a close fellow during their attempt to escape the Aogiri hideout. As after Kaneki defeats Yamori and makes his resolve to protect everyone, Banjou gratefully and grasped by Kaneki's strength, decides to become his follower so he can help him with everything he has got.

Rize Kamishiro
Rize was attracted to Kaneki because of his delicious appearance and himself. Both of them shared many interests. After their date, Rize tried to hunt him down, but failed. At the end, she died and he, heavily injured, went to a hospital, where Dr.Kanou decided to transplant her organs into him.

In Kaneki's mind, during his time locked in Yamori's hobby room, she appeared before him. They had a sensitive conversation about his past and personality. Although she was a figment of Kaneki's imagination, she supported him and strengthened his resolve.

A hallucination of Rize appears to Kaneki earlier in the anime, representing the subconsciousness of Kaneki's ghoul half. She usually haunts Kaneki when he is hungry and needs to eat human meat.

Ken was shocked to see Rize was alive in Kanou's lab as experiment during the raid. Ken looked Rize helpless at staving state as he remember that he received from her origins

Yakumo Oomori
Yamori sees Kaneki as a good "toy" for his hobby of torturing.He sees him as a weak morally-guided boy and makes use of his powerful regenerative ability to satisfy his sadistic pleasures. Ironically, Yamori who inititally believes he had weaken Kaneki was then overpowered and defeated by him, being the catalyst for his transformation

Ms. Kaneki
Ken had close relationship with his late mother who always raised him as single mother. He also enjoyed her home cooking and the hamburgers she made for him.

Uta
Uta helped him make his mask. Due to the fact that Kaneki was one of Uta's valued customers, Uta even offered Anteiku help to rescue Kaneki. Uta along with his clown gang set Kaneki up, betraying him in the end.

Powers and Abilities
Kaneki starts off as weak and not used to fights, with a feeble body that has neither muscles nor flexibility. He has poor reflexes, reflecting his terrible athletic skills when he was previously human. Despite this, he is shown to be very adaptive and a quick learner. He is highly intelligent having the ability of learning martial arts in a short period of time through martial arts books and strict training from Touka and Yomo, making him a competent fighter above the average level.

After being tortured by Yakumo Oomori and accepting his ghoul side all the knowledge and skills he learnt are put to use, he became capable of easily dodging quick attacks, his reflexes and strength were greatly enhance becoming capable of defeating Yakumo with ease. Kaneki is also a tactical combatant, his intelligence and improvisational abilities allow him to challenge foes far more powerful than himself.


 * Rinkaku Kagune: After the organ transplant, Kaneki also inherited Rize's kagune. Rize's kagune is special because it has an abnormal regenerating factor even among the Rinkaku types. While his body is soft and fragile, his kagune focuses on providing enough brute force to take down even the toughest enemies. Since his battle with Arima Kishou, his kagune can produce up to eight tentacle claws that provide him with muscular blades to cut or pierce foes..


 * Kakuja Kagune: After consuming Yamori's Kakuja and various other ghouls and their Kagune, Kaneki obtained an incomplete-Kakuja after his confrontation with Doctor Kanou. Kaneki's Kakuja armor are twin centipede-like tails protruding downwards from his back. The massive tails also have sharp talons on the side. In this form Kaneki's kakuja forms a mask that features a hole for his left eye and a bird's beak over the middle of his face. They provide Kaneki with enough power to even overwhelm Shinohara's Arata Proto. As a incomplete kakuja, Kaneki's loses all aspects of his personality when using this form and as a result fights like a psychotic berserker. Due to this, Kaneki only uses his Kakuja form in desperate situation.

Despite the surgery, Kaneki seems to lack the sense of smell other ghouls have that can differentiate between humans and ghouls, although he is shown to be unaffected by Ghoul-Detecting machines.

Trivia

 * Kaneki has a habit of touching his chin with his left hand when he's lying or feeling uncomfortable. Hide was the one who told Touka about it. He inherited this from his mother.
 * Kaneki was ranked first in the character popularity poll.
 * Kaneki likes reading, beautiful language, intellectual women and hamburgers.
 * Beginning with the Aogiri arc, Kaneki has been repeatedly associated with the number "12" in panels. This is a reference to the tarot card The Hanged Man (XII).
 * Kaneki's role in the story is a parallel to the Goat's child in Sen Takatsuki's book "The Black Goat's Egg".
 * Kaneki's finger cracking was inherited from his torturer Yakumo Oomori.

Quotes

 * "If you were to write a story with me in the lead role, it would certainly be... A tragedy."
 * "This world is wrong"
 * "Why always me?"
 * "If you (Touka-chan) were to die, I will be grieving, y'know...."
 * Touka: "Don't leave me alone..." Kaneki: "I won't."
 * "I'm begging you (Amon), don't make me a killer!"
 * "What's wrong isn't me. What's wrong is the world!"