Jūjika no Rokunin

Jūjika no Rokunin depicts the revenge of the main character on his bullies. In order to defeat several non-human monsters, the boy also became something non-human. Uruma Shun, a sixth-grade student, was named "Experimental body: A" by five of his classmates and was severely bullied and lived in hell. His only peace was with his brother, who loved him, and his parents, who protected him.... . until the five monsters killed his family. When he finally loses everything and faces true hell, a dark "wish" is born inside Shun. He was reborn under the training of his grandfather, who served in a secret unit during WWII. Now, four years later, he appears in front of his bloody enemies. After killing four of his bullies Kyou Shigoku the leader reveals that he has a cult called the revolution club which kills his grandpa and brother before leaving him alone at the crime scene. Uruma was arrested for 5 years and in the time skip lost his memories and joined Juujika.

Uruma Shun (漆間俊)

A kind-hearted high-school boy whose parents were killed and younger brother hospitalized by childhood bullies when he was only 12-years-old, leading him down a path of vengeance on the five. Shun Uruma was bullied by five classmates when he was in elementary school. The abuse was so horrific that it left Shun Uruma physically and mentally scarred. Despite this, he vows to avenge his parents' death and younger brother's comatose on the bullies who have made his life horrible during his high school years. He succeeded in killing four of them and planned on taking down Kyou himself, but the mastermind had formed new allies and was the leader of a cult, which surprised Shun himself. After the match, he failed to kill Kyou, who had escaped with Andou, and was arrested on suspicion of murdering Anzai Zenichi for 5 years. Sometimes after his sentence in prison, Uruma, now 20 years old, somehow lost his memories, met Kitami and joined Juujika.

Shigoku Kyou (至極京)

He is the main antagonist of the manga and is also the leader of Uruma's group of bullies who tormented him in his childhood. Kyou sets himself apart as completely apathetic, cruel, and psychopathic compared to the other four. He is a talented person who has passed the prefectural preparatory school with a perfect score and aspires to the medical school, but he continues to bully him by calling him "experiment" how much he should bully Shun Uruma to commit suicide. He is the earliest to notice Shun Uruma's revenge and is said to seem to enjoy his revenge. After the death of the bullies, it is revealed that he amassed a cult with many followers. He later had Uruma and Jun play a match that led to the deaths of Kaname, Kakaru and Shun Uruma Sr. before escaping with Andou and Momoki. 5 years later, Kyou has longer hair and his scar is healed with his cult now growing in numbers.

Shun Uruma Sr. (おじいちゃん)

He is an elderly man of average height and average build, as well as short white hair and a scar on his left eye. He once belonged to the Kure Naval District 100th Special Land Squadron (commonly known as Kitayama Squadron) during World War II, which was a group of skilled assassins. Knowing that his grandson Shun Uruma, genuinely wanted revenge on the monsters who made his life a living hell,, Grandpa taught Shun Uruma how to murder and torture people. He was later killed by one of Kyou's henchmen, Andou Midori.

Kakeru Uruma (漆間翔)

He is the younger brother of Shun Uruma. He has a cheerful personality and a gentle side, such as petting abandoned cats. It is said that he felt lightly that his brother was being bullied. After the transfer of his brother Shun Uruma was decided, he was in a car with his parents and suffered a traffic accident by Kyou, and became unconscious as a result. He later dies at the hands of Kyou as the latter stabs the former with a knife behind his back.

Kuga Daichi (久我大地)

He is one of the five bullies who mistreated Shun Uruma in their childhood. Shun Uruma and Daichi Kuga are the same in high school, and the big monster continues to mistreat his victim even when they are in high school. Daichi Kuga was a fierce man who won the national junior high school judo tournament in the 90 kg class, and when he mistreated Shun Uruma, he used violence and physically damaged him. Later Shun beats him and later kills him as the fourth victim.

Ushiro Yuuga (右代悠牙)

Ushiro Yuuga is also a member of the group who bullied Shun Uruma. He is a playboy who is called "Yarichin" in the sixth grade of elementary school. Yuuga is involved in crimes such as prostitution and drug trafficking in high school. In addition, Yuga is a deluded teenager who confined a girl by the name of Karen Sakuraba at his home and sexually assaulted her. Later he is tortured by Shun and Karen, eventually dying as the second victim.

Madoka Hiro (円比呂)

He is a member of the group that bullied Shun Uruma. He is a fanatic who can lick his shoes without hesitation if he is to be recognized by Kyou. One of his special talents is creating poisonous drinks and forcing people to drink them. He attacks Shun Uruma at the school festival in order to earn Kyou's approval, only to fail and instead raping Kaname as a result of her eavesdropping on his plan to attack Uruma. He later becomes Shun's third victim.

Senkouji Katsumi (千光寺克美)

Senkouji Katsumi is also a member of the bullying group. He was originally on good terms with Shun Uruma until he resorted to bullying his former friend by shooting Shun with an air gun. Senkouji later became the first target of his victim's revenge, dying after being tortured severely by Uruma.

Chizuru Azuma (東千鶴)

A girl from Shun's class who develops feelings for him.The time skip has her return in a new job with longer hair and reunites with Uruma, who lost his memories while working under Kitami.

Kaname Shirakawa (白川要)

The younger twin sister of Jun and childhood friend of Uruma. She was raped by Hiro Madoka and seemingly died at the hands of Kyou's cultists, only to have ostensibly survived her attack and reconcile with Uruma 5 years later at the clinic.

Jun Shirakawa (白川純)

The older twin brother of Kaname, he is very protective of her and is also a childhood friend of Shun. At some point in the story, when his younger sister gets raped, he mistakenly believes that Uruma was responsible for his younger sister's rape, causing him to join Kyou's cult just so he could inflict suffering on Uruma before realizing his mistake and later switching sides to make up for the suffering he caused him. His fate regarding the incident involving him, Kyou's cult, and Uruma was left ambiguous until he made a phone call through Andou's phone to Kitami. It was then revealed that he abused multiple girls into donning his late sister's appearances while being in relationships with them.

Anzai Zenichi (安西全一)

A cop who investigated Shun and the bullies before getting killed by the former later on in the story. His recording of his incident with Uruma would later allow his assistant, Oota, to arrest Uruma and prevent him from committing his final revenge, leading to the second part of the story.

Ooto Asako (太田朝子)

Anzai's partner involved in the case revolving around the accident that claimed the lives of Shun Uruma's parents. She is described as easy-going and stupid despite her job as a police officer. Furthermore, she is also very kind as she offers accommodation to Uruma when her house was burnt down by Kuga Daichi. After discovering Uruma's true colors and her involvement in Anzai Zenichi's death, she becomes more serious and cold towards Uruma and later arrests him as she is a suspect in the suspicious death of her former mentor. Still, she wanted to help Uruma get his sentence reduced or canceled if she would tell about what happened in the old elementary school and Uruma's family case and know if it was really him who voluntarily eliminated Zenichi. After Uruma is sentenced to prison, Asako wants to investigate further the Uruma family case to find out not only all the mysteries of it but also why it is connected to other cases. Five years later, she becomes a police inspector and begins to investigate the "Juujika-san" case together with Anzai Mizuki, Zenichi's wife.

Ganno

A minion of Ushiro who was sent by the psychopath to rape Azuma Chizuru. Being gigantic for a teenager himself, he is also very abusive and misogynistic as he views women as sex objects and even threatens to beat those who dare resist his sexual advances. At some point, when he attempts to attack Azuma, he is confronted by "Bikerman" (who is actually Shun Uruma wearing a bicycle helmet to cover up his identity) and the bigger man seems to have gained the upper hand in their fight only for the tables to turn once Uruma dislocates the bigger monster's joints, permanently.

Maki

A prostitute who works under Ushiro.

Daki Kawashima

A servant of Ushiro.

Andou Midori

A member of the Revolutions Club. Being the most loyal cultist out of the four (including Miguel, Momoki, and Nogi), he is very talented in not only combat, but also torturing other people. Ever since Kyou taught him how to properly torture people, he has been loyal to the psychopath ever since. He is responsible for not only kidnapping Shun's younger brother, Kakeru, but is also responsible for mutilating the young child's leg and later murdering Uruma Shun Sr. After the events revolving around the match, he, Kyou, and Momoki, all escaped before the police arrives to arrest them. Five years later, he is seen, along with Momoki and two other unidentified researchers, meeting up with Shigoku Kyou during a meeting. He later dies at the hands of Uruma by being burned to death after being tortured.

Miguel (美外留)

A member of the Revolutions Club. Being a tall and muscular man, he is very charismatic and well-mannered in spite of his appearance. However, like the other members of the Revolutions Club, he is just as twisted, cruel, and violent as they are when it comes to torturing any members of the club. He gets his left eye gouged out by Uruma (which didn't affect him that much) before attempting to twist his head, although he later gets killed off by Gramps as the elder man rips out his vein, instantly killing him.

Sana Momoki

A member of the Revolutions Club. Being the most attractive and quietest member of the Revolutions Club, she is seen witnessing all the events revolving around the Revolutions Club. In addition, she later takes Uruma to his and Kyou's former elementary school to a "match". While the match begins, she mutilates Kaname twice when Jun lost 2 rounds of "Rock, Paper, Scissors" before wheeling her lifeless body to the older twin brother. She also holds Kakeru hostage before Andou attempts to kill the both of them, only for her to get out of the way before she gets killed. She is later seen in her attempt to protect Kyou from a berserk Uruma who kicks her in the face, knocking her unconscious. Despite this, she managed to escape the gym, along with Andou and Kyou, before getting arrested by the cops. Five years later, she is seen entering a room with Andou and two other unidentified researchers to meet up with Kyou.

Takashi Nogi

A member of the Revolutionary Club. Being the shortest member of the Revolutions Club, he is very bad-tempered and prone to using violence towards anyone in general. He was seen holding Kakeru hostage with a knife when threatening Uruma if he didn't participate in the Rock-Paper-Scissors match with Shirakawa Jun. At some point, he repeatedly kicks Uruma in the head while berating him after the latter's remaining family members die before the short man gets his face ripped off by the surviving member, who also punches the cultist in the head, knocking him to the ground and effectively killing him.

Karen Sakuraba

A girl who was kidnapped and abused by Ushiro, she later gets her revenge on her abusive boyfriend before committing suicide.

Mr. and Mrs Uruma

Shun's parents who were killed by the bullies.

Anna Sugisaki (杉崎杏奈)

Kyou's cousin and Kuga's girlfriend who is later killed by the latter.

Kitami Kougo

The leader of "Juujika-san" who helps people kill their tormentors as long as they pay him a lot of money. The mysterious leader of the group, he disguises his assassination business as a "clinic" so that he could be able to run it without getting caught by the police. Uruma ends up working for him ever since the post-timeskip ostensibly to make up for his failures in killing Kyou (though it was revealed that he lost his memories of everything that happened in the past, implying that he joined Kitami as a way of making a living).

Mimi Kawana

Kitami's assistant.

As of March 2022, the manga had over 1 million copies in circulation.[19]

• Official manga website (in Japanese)
• Jūjika no Rokunin (manga) at Anime News Network's encyclopedia