Naki

Naki is a ghoul, who was imprisoned in Cochlea until Aogiri Tree's invasion on the prison. He was liberated by Aogiri Tree due to being a direct underling of Yamori, and supposedly his right hand man. He is almost always accompanied by the Twins Gagi and Guge.

He eventually climbs the ranks within Aogiri, and has become an Executive in his own right. The number of Ghouls following him has grown considerably, forming a gang known as the White Suits for their distinctive style.

Appearance
Naki has always appeared wearing a white suit. Naki's hairstyle is neatly sorted into three parts, with his left and right side brushed to their respective side and the middle section's hair pushed back, revealing his forehead. The most distinguishing feature of Naki is probably his eyes, which have always been shown with pitch-black eye-shadings.

In the manga, Naki is missing two small portions off his left ear. In the anime, however, this is changed to two black earrings.

After the time skip, Naki's hairstyle is combed to one side, fully to the back, mimicking Yamori's.

Personality
Naki has been shown to be a confident individual, boasting about his strength and that he is Yamori's right hand man. Like Yamori, Naki is shown to have a twisted mindset; although not as cruel as Yamori, Naki is depicted to show his personality permanently with no efforts to hide it. Though impulsive and easily irritated, Naki is shown to be very emotional and trusting, perhaps to the point of being naive. He highly respects Yamori and was devastated to learn that Yamori had been killed while Aogiri Tree was breaking him and other ghouls out.

Naki has a childlike personality, believing that having helped Yamori with counting money and running errands make him a responsible person worth others' respect. His lack of general knowledge portrays him as a typical ghoul who's had suffered from the lack of education due to their status as a ghoul.

He views loneliness as the most painful, and as such risks his life to protect his comrades to never feel the loneliness he felt when he got out of prison just to hear Yamori had died and left him alone.

He also seems to have copied Yamori's habit of finger cracking (although he cracks his middle finger instead).

Past
Naki first encountered Yamori in the 13th Ward, when he challenged the other Ghoul without knowing his reputation. He lost the battle, but afterwards begged to be allowed to follow him and began to call Yamori his "Big Bro" as a sign of respect. He would then begin imitating Yamori's style and carry out errands for him.

Raid of Kanou's Lab
Along with Matasaka Kamishiro, he is first seen attempting to kidnap the nurse of Kanou General Hospital, Taguchi, and then fight against Kaneki's group which have similar purpose, when he realized that Kaneki was the One-Eyed Ghoul who killed his Big Bro, he begins to cry. After briefly fighting with Tsukiyama, he and the Aogiri members leave the area, taking away the nurse successfully.

Later on, he and Eto are waiting for Tatara to interrogate Taguchi about Kanou's whereabouts.

He takes part in the raid and is seen interrupting the fight between Tsukiyama and the Yasuhisa sisters claiming that he would be the one to take Kanou, calling him a "mad scientoast". He engages on Tsukiyama and yells about how he damaged his suit the last time they fought. As they fight, the ghoul investigators arrive in the area and Naki decides to accept Tsukiyama's offer to become a temporary ally so he wouldn't need to bother fighting two different enemies. He overwhelms Amon but then is easily defeated by Akira Mado who later uses a RC suppressant grenade. Unable to use his kagune he still jumps in front of one of his twin comrades saying that he wouldn't let the others die. Even though he received several blows he was still able to deliver a kick to Akira and bite her leg. Getting attacked by an enraged Amon and unable to stand on his own he escapes while being carried by his comrades.

Post-20th Ward One-Eyed Owl Battle
He is briefly glimpsed in a playground, accompanied by his Twin goons. All three are seated on a see-saw, while Naki cries.

Auction
When Big Madam hires Aogiri to provide security for the event, Naki is mentioned to be among those selected for the job. When Juuzou Suzuya reveals himself and begins attacking, Ayato shouts for Naki and Miza as chaos erupts.

Ordered to secure an escape route, Naki charges into battle along with his followers and begins to kill the humans in his path. He quickly gains the upper-hand, with his forces joined by Miza and her team. When confronted by Akira Mado, he notes that he recognizes her face but doesn't remember her name.

Naki finds her quinque to be a pain to deal with, struggling to close the distance between them. He concludes that the best chance to get close is when the Fueguchi quinque is fully extended and charges towards her at the next chance; the opening, however, was a trap Akira had set purposefully. He is impaled from behind and collapses on the ground, badly wounded. She lectures him about being trapped in the past, still clinging to the memory of "Jason" and thus is unable to change. This enrages him, and Naki thinks about how everything that matters to him and his strength are from the past. Investigators surround him and open fire, but Gagi and Guge leap in front of him and shield him with their bodies. As he begs them to stop, the rest of the gang goes wild and begins taking out the Investigators with renewed strength. Horrified, Naki clings to the dying twins while begging them not to leave him alone. Along with the rest of the White Suits he rallies and attacks the Doves to avenge his subordinates, killing several investigators before being wounded. He is later saved from being finished off by Ayato Kirishima.

He continues to fight, this time alongside Ayato and is later seen attempting to convince Ayato to retreat in in face of the arrival of Arima Squad and S3.

Rosewald Investigation
Kanou is seen discussing about Gagi and Guge with Naki, hoping to gain his consent to use the twins' kakuhou for experiments. He simplifies what he's saying to Naki due to the ghoul's lack of proper education, telling him that he will definitely revive the twins "in a sense" which led Naki to thank him and share his joy with other fellow white suits.

Root A (Anime)
He is first introduced as a prisoner being transported by CCG, when the van comes under attack by a group led by Ayato and Kaneki. Naki breaks free out of the overturned van, but is hysterical and begins to attack Ayato. He screams for Yamori, and throws a tantrum in front of the puzzled rescuers. When Ayato calls him an idiot, he responds with anger and attacks them again.

Later on, he learns that Yamori had been killed during the previous battle against CCG and becomes hysterical with grief. He smashes up a toy store, and throws himself to the ground while his twin lackeys attempt to calm him. Ayato storms off in disgust, while Kaneki watches the tantrum from a distance. Naki begins trying to write Yamori's name in crayon, but is unable to do so and becomes increasingly confused and upset. Kaneki joins him, and teaches him how to write "Yamori" in an act of kindness. As the half-Ghoul tries to leave, Naki thanks him and tells him he is a really good person -- unaware of Kaneki's role in his beloved "Big Bro"'s death, Naki is then again shown in Aogiri Tree's Cochlea invasion, he is shown to be giving Akira and Amon trouble, he is then injured by Akira but he manages to bite a chunk of her leg which then results in Amon sending him flying using his quinque.

Yakumo Oomori
Naki claims to have been Yamori's right hand man, and highly respects him for his strength. He is completely devoted to him, and continues to grieve for months after learning of his death. Surprisingly, Yamori showed unusual kindness and patience towards him compared to others -- explaining things in simple terms for him, and giving him birthday presents.

Shuu Tsukiyama
During the Raid on Kanou's Lab, Naki and Tsukiyama formed a temporary alliance after dueling a bit due to the CCG investigation team's interference. Naki believes Tsukiyama to be a good guy (while Tsukiyama sees him as a trusting fool) but doesn't appreciate him talking in French (mistaking it as English).

Ken Kaneki
Naki has hateful feeling towards Kaneki, knowing he was the one responsible for the death of Yamori.

In Tokyo Ghoul √A he does not seem to know that Kaneki killed Yamori, and actually thinks that Kaneki is a good guy.

Akira Mado
They have fought twice, during the Kanou's Lab Raid and at the Auction Raid a few years later. Though Naki seems to remember having faced Mado before, he does not recall her name.

Hinami Fueguchi
They seem to be familiar with each other, although Naki misreads her name when she is recruited by Aogiri Tree.

Ayato Kirishima
Despite not seen interacting with one another almost completely, it is shown that Ayato expresses concern for him as seen when he disobeyed his orders and rushed to Naki's aid when Naki was overwhelmed by the doves.

Miza
They seem to be familiar with each other, and were partnered together during the Auction Raid.

Powers & Abilities
Although he has been noted to pale in comparison to Yamori, Naki is a moderately powerful ghoul, having fought skillfully against numerous dangerous ghouls and strong ghoul investigators in combat.
 * Koukaku Kagune: As a Koukaku user, Naki utilizes his kagune as a broadsword-like blade on his right arm. He has shown proficiency in battle, killing numerous Investigators during the Auction mopping-up operation and was shown giving Amon a lot of trouble during their battle and also being able to stand against Shuu Tsukiyama in battle as well.

Trivia

 * In one of Ishida's drafts, it is revealed that the scarring on his ears was from being bitten by Yamori.
 * In the anime, he is portrayed as illiterate while the manga shows he can read and write, albeit poorly.
 * Like Kaneki, Naki inherited the finger cracking habit from Yamori.
 * His name has the same pronunciation as 泣き(naki), which means weeping or lamenting.
 * In Tokyo Ghoul Trump, he is jointly featured with Gagi and Guge, as the "Two of Diamonds".