Ayato Kirishima

"The world is about power. Everything is decided by the superiority or inferiority of each person's power. Get that through your thick skull, you idiot. You're weak. That's why you're going to lose. Just like my father."
Ayato Kirishima

Ayato Kirishima is Touka Kirishima's younger brother and goes by the pseudonym Black Rabbit.

He grew up with his sister in the 20th ward, but at some point, he left her. According to Kazuichi Banjou, Ayato subsequently began wandering all the wards of Tokyo, bringing destruction and chaos upon them, until his unique powers and abilities caught Tatara's attention. Ayato was then recruited into Aogiri Tree, where he served as an executive before its downfall.
Later, he joined the new Goat organization under the command of the One-Eyed King.

Appearance
Ayato was a thin young man with dark blue eyes and messy dark blue hair that fell over his eyes. He bore a striking resemblance to his sister and had a rebellious, rough appearance. He wore a long-sleeved black leather jacket with a hood, 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.
In the anime, Ayato was primarily seen wearing a black mask with spikes, as well as a black overcoat with a white fur collar.
After the time skip, Ayato had visibly grown and was seen wearing black ankle boots and a long black coat over his clothes.
Ayato possessed several black masks. The first one had red eyes and a grin with sharp teeth, which he used during the Aogiri Arc. His most frequently seen mask had a rabbit design, earning him the nickname "Black Rabbit". During the auction, he wore a very basic, vaguely conical mask that only covered the lower half of his face.

Personality
Ayato was an arrogant and impetuous teenager with an impulsive personality similar to his sister's, and usually sported a scowl or a menacing smile. Aside from physical appearance, he shared many similarities with Touka, such as a tendency to use frequently rude or inappropriate language. He had a habit of kicking people for trivial mistakes, like when Kaneki didn't treat him properly or when Banjou didn't return his missed calls. However, he seemed more severe compared to his sister, but admitted to being surprisingly "kinder" than his superiors at Aogiri. He firmly believed in the idea that "the weak perish and the strong survive," a belief triggered by the death of his parents. Ayato harbored deep resentment towards his father, Arata, for abandoning him and Touka when they were young. Ayato even stated that the only reason for his hatred of Kaneki was his resemblance to Arata. Kaneki also pointed out that Ayato cared deeply for Touka, even if unconsciously, as demonstrated when he beat her first after letting her suffer a slow and torturous death at Yamori's hands. Later, he also adopted her pseudonym, "Rabbit," so that the CCG would hunt her instead of Touka; Ayato also seemed to have a certain fondness for rabbits.
Three years later, there was a reduction in most of the mannerisms and habits that Ayato displayed when he was younger; he became much less grumpy, unpleasant, and arrogant, and even developed a rational and approachable way of speaking. Ayato also developed a sense of concern, as well as an instinct to protect his subordinates, demonstrated when he refused to leave Hinami behind at the auction and when he disobeyed Tatara's orders and went to support Naki when the latter was outnumbered against the Doves.

However, he still retained some of his old traits, such as ruthlessly massacring ghoul investigators and engaging in violent fights. He tends to hide his more sensitive side, denying that he wanted to visit his niece.