Ayato Kirishima.

Ayato Kirishima (霧嶋 絢都, Kirishima Ayato) is Touka Kirishima's younger brother and goes by the alias Black Rabbit (黒ラビット, Kuro Rabitto). He grew up with his sister in the 20th ward, but at some point he left. According to Kazuichi Banjou, Ayato subsequently began to wander all the wards of Tokyo, bringing sheer wreckage and chaos upon them, until his unique powers and abilities caught Tatara's eye. Ayato was therefore recruited into Aogiri Tree, where he served as an executive before its downfall. Later, he joined the new organization Goat under the One-Eyed King.

Ayato was a lean young man, with blue eyes and long, messy blue hair that swept down in front of his eyes. He bore a striking resemblance to his sister and had a rough-looking, rebellious image. He wore a hooded, long-sleeved black leather jacket, black pants, and knee-high black boots. Ayato also had a piercing in his left ear and usually wore a ring on the pinky finger of his right hand. After the timeskip, Ayato had grown noticeably taller, and was seen wearing shin-high black boots and a long, black coat over his clothes.

Ayato possessed multiple black masks. The first one had red eyes and a sharp-toothed grin, which he used during the Aogiri Arc. His most frequently seen mask bore a rabbit design, earning him the moniker of "Black Rabbit." During the auction, he wore a very basic, vaguely conical mask which covered only the lower half of his face.

Ayato was an arrogant, brash teenager, with a similar hot-blooded attitude resembling his sister's, while he normally displayed either a scowl or menacing smirk on his face. Other than his physical attributes, he shared many similarities with Touka, such as his tendency to use language that is often uncouth or inappropriate. He had a habit of kicking people for the simplest mistakes; such as when Kaneki failed to address him with the desired honorific, or when Banjou did not return his missed calls. However, he seemed to be harsher compared to his sister, but admitted himself to be surprisingly "softer" than his Aogiri superiors. He was a firm believer in the notion that "the weak perish and the strong survive," which was triggered by the death of his mother and father. Ayato bore deep grudges against his father, Arata, for abandoning him and Touka when they were young. Ayato had even stated that the whole reason for hating Kaneki was his resemblance to Arata. It was also pointed out by Kaneki that Ayato cared deeply for Touka subconsciously, as shown when he beat her down first rather than allowing her to suffer a slow, torturous death from Yamori. Later on, he also took her alias, "Rabbit," so the CCG would hunt him instead of Touka. Ayato also seemed to have a soft spot for rabbits. Three years later, most of the mannerisms and habits Ayato once displayed in his youth had diminished; he became far less ill-tempered, obnoxious, and arrogant, and even developed a rational, approachable way of speaking. Ayato also developed a sense of concern and an instinct to protect his subordinates, shown when he refused to leave Hinami behind at the auction and by disobeying Tatara's orders to back up Naki when he was outnumbered by the Doves. However, he still retained a few of his old traits, such as relentlessly slaughtering ghoul investigators and engaging in violent brawls.

Ayato resided in the 20th ward with his sister Touka, under the care of their father, Arata Kirishima. Arata lived his life like humans did; he usually took Ayato and Touka to the library to study, and even convinced them to eat food offered by humans; for he believed that ghouls should try to blend in with human society by adapting their behavioral patterns. Ayato, however, supposed that it was solely a human's world, and that ghouls were not “normal.” He and Touka also cared for a bird, where Ayato was shown to dislike earthworms and insects. One night before Arata set out on his regular scavenging routine, Ayato made a promise to him that he would protect Touka whenever she was in trouble. After Arata never returned, Ayato assumed that his father had died by ghoul investigators finding and killing him. Touka and Ayato visited a woman named Satou to tell her of their father's disappearance. She offered them human food, but when they refused, Satou stuffed the food in Ayato's mouth, and both siblings were sold out. They managed to escape as Touka used her kagune to kill the investigators. Ayato's perspective on humans changed immediately; he concluded that none of what they went through would have happened if they hadn't gotten involved with humans. After running away from home, they found Anteiku, where they were taken care of by Yoshimura. As they grew up, the siblings became stronger, to the point where Ayato started displaying violent tendencies. When Touka started school and met Yoriko, Ayato told her that interacting with humans was foolish; for they could not be trusted under any circumstance. Believing they might end up like Arata, Ayato left Anteiku in search of more power. He then wandered the wards of Tokyo, such as the 14th ward; where he took away multiple feeding grounds from the ghouls there.

Ayato was first seen at the Aogiri Hideout in the 11th ward, enraged by the fact that he had sent Kazuichi Banjou on a mission to capture Rize Kamishiro, but Banjou wasn't answering his phone calls. Ayato, thinking Yakumo Oomori and Nico would capture Rize before him, decided to visit the 20th ward. He briefly discusses a little of his history there with an unnamed Aogiri member. Ayato barged into Anteiku upon hearing Banjou tell Ken Kaneki to tell Rize to run away from the incoming danger. He kicked Banjou in the arm, breaking his bones, and threatened to beat him again. Ayato was suddenly confronted by his older sister Touka Kirishima, and when asked where he had wandered off to after leaving her life, Ayato said he had been "studying the world," for he would never proclaim himself to be a "peaceful idiot." Ayato was disappointed to see Yamori at Anteiku as well, but when Nico pointed out that Kaneki was indeed the one who smelled like Rize, Ayato cooperated with Yamori to capture Kaneki. When Touka resisted their attempt to take Kaneki, she fought Yamori but was confronted by Ayato. Ayato, punching her in the face, compared Touka to their dead parents, calling her a "weakling." Touka thrust her kagune at him, but he blocked the attack with one of his wings. With his own kagune activated, Ayato vowed to show her that ghouls were truly superior to humans. Ayato then effortlessly beat her down, subsequently ordered Banjou to stuff an unconscious Kaneki into a bag, and headed back to the 11th ward. When asked if they should take Touka as well, Ayato refused, saying she would only weigh them down.

in the world there are two sides constantly confronting each other - ordinary people and ghouls. ghouls are the same people, a carnivorous and cannibalistic species, capable of feeding only on people or other ghouls. They are as similar to people as possible: as a rule, they have the same external appearance and the same developed intelligence, but their diet, mentality and internal structure are slightly different from humans. In rare cases, human and ghoul individuals are able to have offspring, and ghoul organs can be transplanted (with a low chance of success) into a human body. Because of their diet, ghouls are persecuted by the forces of nature CCG (organization for the killing of ghouls), deprived of any rights in human society, including the right to life. ghouls are able to feed only on human flesh or the flesh of other ghouls. The taste buds of ghouls are also different from humans, which is why the taste of ordinary food causes disgust and nausea in ghouls. If a ghoul tries to eat human food, it will subsequently experience a strong urge to vomit. Forcing itself to eat such food will result in the degradation of its physical condition. Ghouls, unlike humans, do not need to eat frequently. They are able to survive by eating only once every one or two months. However, some ghouls eat much more often for their own pleasure. Despite the fact that ghouls can go without human flesh for two months, some of them are able to eat up to eleven people at once in a short period of time. Such ghouls are also known as "devourers", one example of which was Rize Kamishiro. In addition, food is "fuel" for the use of ghouls' special abilities; frequent release of kagune and regeneration of wounds require more intensive nutrition. Ghouls have high physical abilities, which makes them much stronger than an ordinary person: by striking with sufficient force, they are able to throw a person into the air or pierce his body through and through.

In addition, the height of their jumps can reach several meters. Under normal conditions, ghouls have a high regenerative capacity. Minor wounds and fractures heal in a matter of hours; more serious wounds heal within a few days if the ghoul has a sufficient supply of food. Kagune (赫子, kagune) is a ghoul's hunting organ, used as a weapon. It is usually blood-red or black in color, flexible like a stream of water, but also hard and durable. After releasing the kagune, the ghoul's body is strengthened: it becomes more resilient, its movement speed increases, and its reactions become sharper. The kagune is made up of Rc cells, which circulate in the ghoul's body like blood. They are capable of acquiring a hardness similar to tooth enamel; in addition, they can be described as "liquid muscles". RC cells are released through the kakuhou located on the back, after which they form the kagune. After being released, the kagune takes on the state of a "controlled muscle", which the ghoul can either strengthen, making it stronger, or soften/relax. The size depends on the quality and quantity of Rc cells in the owner's body, while its shape is influenced by the ghoul's intelligence, creativity, and imagination. Kakuhō (赫包, kakuhō) is a sac-like organ that only ghouls possess. The kakuhō is designed to store RC cells. RC cells are recreated during the ghoul's feeding, after which they are transported along with the blood to the kakuhō, where they are subsequently accumulated. RC cells, piercing the skin, can be released through the kakuhō by the ghoul's will or during periods of intense excitement. Once manifested, they take the form of a kagune Kakugan (赫眼) is a ghoul's eye, with a red glowing pupil and black sclera. Often, red glowing "vessels" diverge from the kakugan's pupil, which are actually RC channels that.

One-Eyed Ghoul (隻眼の喰種, Sekigan no Gūru) is a human-ghoul hybrid that possesses the physiology of a ghoul. Most ghouls are either completely unaware of them or believe their existence to be an urban legend. Quinx (クインクス, kuinks) is a human with a quinque implanted in their body. Because the quinque resembles a kagune, quinxes can be mistaken for ghouls or half-ghouls. Quinke (クインケ, kuinke, labeled as "former enemy") is a weapon created from a ghoul's kagune. Made from a kakuhou, the quinque emits electrical impulses that stimulate the kakuhou, allowing control of the kagune. The Quinque can be created in various forms, such as bladed weapons/firearms or even armor, with most retaining some of the characteristics of the original Kagune. Another difference between the Quinque and the Kagune is that the Quinque can no longer evolve and absorb Rc cells.