Block 2, Cell 6

Rokurouta Sakuragi (桜木 六郎太, Sakuragi Rokurōta)

Voiced by: Rikiya Koyama

Also known as "Bro" (アンチャン, Anchan) from the fact that he is called "everyone's big bro," he was admitted for assaulting and injuring an American soldier. He is a senior member of block 2, cell 6. He is about to be released from prison, but for some reason he is locked up behind bars. His dream is to become the world boxing champ and to show filial piety to his mother, who raised him despite the death of his father and five older brothers. He teaches the six inmates, who were defeated by reality and had lost their goals and dreams, to live strongly with "love and courage."

He later escapes and lives with Setsuko, a nurse with whom he had a mutual love. At the end of chapter 1, after being stabbed with a knife by Ishihara due to Sasaki's trickery, he is shot dead by American soldiers after a word from Sasaki. After his death, the bullet found in his body and his will were passed on to his inmates. Later, it is revealed that he held a secret that could affect Ishihara's career.

In chapter 4, it is revealed that the reason he was admitted was because he was invited by Tetsu Sakota, a senior at the boxing gym he attended, to take the blame for shooting and killing his opponent, an American soldier who came to retaliate against him on his way home from a betting match at an American military base. Later, he learns the truth about Sakota, who has been admitted, but he still continues to believe in him, and as a result, he is noticed by Ishihara. Then, with only a few days left on his sentence, a fateful encounter with six boys awaits him.

Mario Minakami (水上 真理雄, Minakami Mario)

Voiced by: Shun Oguri

Admitted for attempted murder, he is a violent-tempered man who will risk his life for his friends, no matter who they are, and is short-tempered at worst and big brotherly at best.

He is the slowest of the six to be released from prison. For one reason or another, he had his right fist crushed, but at the end of chapter 2, he underwent a major operation that may or may not cure him, and he recovered completely. Thereafter, he inherits Bro's will and aims to become a world boxing champion. He meets Bro's mother by chance at his grave and entrusts her with a pair of boxing shoes as a memento. As he grew up, he began to resemble Bro, and from chapter 3 onward, his friends mistook him for Bro for a moment.

At the end of chapter 3, after saving Setsuko, a former love of his, from the clutches of the foreign con group, he is mortally wounded, but is rescued by Soldier and survives as he relies on Bro's words that continue to live inside him for emotional support.

In chapter 4, he has almost recovered from the wounds he sustained at the end of chapter 3, except for his left eye, which was blinded, now training in Hawaii with the support of Cabbage and Jimmy to fulfill the promise he made to Bro. After fulfilling his "promise to Bro" with Sakota, he returned to the U.S. and set off on a journey of living a life of leisure with dignity to find his own happiness (unlike the other five, Mario is the only one for whom a definite ending is not depicted).

Noboru Maeda (前田 昇, Maeda Noboru)

Voiced by: Romi Park

Also known as "Turtle" (スッポン, Suppon, lit. Chinese soft-shelled turtle) from the fact that his weapon is biting with his own teeth and not letting go (like a turtle), he was admitted for repeated crimes of grand larceny. He was orphaned by the atomic bomb dropped on Hiroshima. He is short and has 10-yen bald spots on his head. He is a honey-mouthed businessman by nature with a dream of becoming a millionaire. He usually hangs out with Cabbage and Scam, and especially with Scam, with whom he has a close family relationship.

After his release from prison, he worked as a black marketeer and then as a money lender, and continued to support his friends, mainly financially, by making use of his talent as a trader. In chapter 4, he starts his own company, Maeda Finance, and after seeing through his "promise to Bro," he has grown to own two buildings of his own and is on the verge of achieving his dream of becoming a wealthy man.

Tadayoshi Tooyama (遠山 忠義, Tōyama Tadayoshi)

Voiced by: Takaya Kuroda

Also known as "Soldier" (ヘイタイ, Heitai) from his dream to serve, he was admitted for violent behavior and false imprisonment. He is a rowdy giant with chivalrous qualities who is frightening when offended. He has a clear dream of becoming a soldier. While in prison, he submitted a request to join the Self-Defense Forces, and was the first to be released in the form of enlisting in the Self-Defense Forces. He has cuts on his right eye and forehead. He was raised by his mother, who told him that his father was a soldier.

Later, he becomes compatible with and marries Joe's sister Meg, but at the end of chapter 3, he rushes to the U.S. military base in pursuit of Setsuko and the mortally wounded Mario, but is mistakenly identified as an arsonist when he is caught by police officers at the scene of a blaze. As a result, he served time in prison and was discharged from the JSDF after being charged with the crimes of the foreign con group alone in order to help Mario.

In chapter 4, he is released from prison thanks to Scam's efforts, and he takes a physical risk to stop Sakota, who has lost his mind in revenge for the attack on the Aritou Group, and takes him to Bro's graveside to tell him of his death.

After seeing through "Bro's promise," through Turtle's introduction, he takes a position as a jailer at the special reformatory, and from his position, he makes an effort to be a source of emotional support for the inmates. Meanwhile, in his personal life, Meg is pregnant, and he enjoys a small measure of happiness.

Ryuuji Nomoto (野本 龍次, Nomoto Ryūji)

Voiced by: Keiji Fujiwara

Also known as "Scam" (バレモト, Baremoto) from his favorite motto, he was admitted for fraud, embezzlement, and luggage theft. His father was killed in Manchuria and the confusion after the war caused him to distrust people, but he was saved by his friends and strangers.

He always wears glasses that seem to slip off and is concerned about his virginity. He and Turtle are very close and have a family-like relationship. After some twists and turns, he studied under Takada, a prosecutor (and later a lawyer), and decided to become a lawyer himself while attending night school. He has a mother and two younger brothers (Tatsuo and Kazuo) who look just like him.

In chapter 4, he is working hard to lighten the charges of Soldier, who alone has been charged with the crimes of the foreign con group. However, he has yet to pass the bar examination and is preparing to take the exam for the eighth time.

Jou Yokosuka (横須賀 丈, Yokosuka Jō)

Voiced by: Tatsuya Hasome

Also known as "Joe" (ジョー, Jō), he was admitted for assault, injury, and illicit sexual relationships. He is an orphan and has a younger sister named Meg. He is a handsome-looking mixed-race boy with blond hair and blue eyes, with moles around them. As a child, he and his younger sister Meg were left at the doorstep of an orphanage for mixed-race children by their mother, where they grew up. Because of his superior looks, he was noticed by the female director and sexually abused. After being admitted to the orphanage, Meg was taken in by her adoptive father, and they were separated for a long time without knowing each other's whereabouts, but were later reunited. After learning of Soldier and Meg's love for each other, he begins to look out for him.

He has a dream of becoming a singer and was a member of a band. In chapter 4, he is making a living as a singer touring bars and other venues, and he offers a helping hand to Sakota, who is leading a life of crime, to fulfill a promise he made to Bro.

After seeing through his "promise to Bro," he finally makes it big as a singer, fulfilling his dream and becoming so famous that he has a following of fans.

Mansaku Matsuura (松浦 万作, Matsuura Mansaku)

Voiced by: Tomohiro Waki

Also known as "Cabbage" (キャベツ, Kyabetsu) from the tattoo of an Ariocarpus retusus on his right shoulder, he was admitted for delinquent behavior such as assault, bodily harm, and drunkenness. He is a slow-witted, overly kind, gluttonous, and muscular man.

Compared to his fellow inmates, he had a hard time finding his path, but through Aritou's introduction, he found a way to make a living as a professional wrestler.

In chapter 4, he is in Hawaii with Jimmy, supporting Mario as he tries to make a fresh start, and keeping in touch with the other four via international phone calls.

After seeing through "Bro's promise," he returned to the U.S. and continued his career as a professional wrestler "Mammoth Matsuura," and married Ruriko.

Friends

Setsuko Koike (Norimatsu) (小池（則松） 節子, Koike (Norimatsu) Setsuko)

Voiced by: Shihori Kanjiya

Nurse. She shelters the escapees of the reformatory. She was also Bro's lover. Later, when Mario had feelings for her, she accepted them once, but left him shortly after. She married Yasurou Norimatsu and had their first son, Takurou.

After the twists and turns of the foreign con group, in chapter 4, she is leading a fulfilling life as a nurse at Higashida Hospital, despite the hardships of being a single mother.

Lily (リリィ, Ririi)

Voiced by: Kaori Yamagata

A prostitute who frequents the U.S. military base. She is the mistress of a high-ranking officer, and takes advantage of her position to help the seven inmates in their time of need. When the U.S. military officer was repatriated, her secret savings were also taken away from her, and she lost everything at one point. After living in Mr. Sugi's house as a live-in domestic helper, she opened her own restaurant, and since then she has been a great support as an older sister to the six inmates and Meg.

Meg Yokosuka (横須賀 メグ, Yokosuka Megu)

Voiced by: Megumi Toyoguchi

Joe's younger sister. When Joe was 12 years old, she was taken in by her promiscuous adoptive father through the guidance of the orphanage's female director while he was admitted at Block 2, Cell 6. On this occasion, Joe, who was concerned about Meg's safety, escaped from the reformatory, broke into the orphanage, and tried to get her out, but Meg, considering her brother Joe's position, deliberately shunned him coldly and chose to live with her foster father. Born July 7, 1942.

She was sexually abused by her adoptive father and ran away at the age of 15 to work in a cabaret and other establishments.

She later helped Lily in her restaurant. Then, she and Soldier become compatible and get married.

When Soldier was later convicted of a crime against the foreign con group and served time in prison, she was not upset at all and continued to trust him, and after seeing through Bro's promise, she becomes pregnant with Soldier's child and enjoys a little happiness.

Ruriko (ルリ子)

Appears from chapter 3 onward. She is a third generation Japanese American from Hawaii. She came to Japan to train for homemaking. She was assigned to work in compulsory service in stopping motorcycles under Turtle. She later develops feelings for Mario, but sensing his lingering feelings for Setsuko, she voluntarily backs out. Later, at the end of chapter 4, she married Cabbage.

Iwasaki (岩崎)

Appears from chapter 2 onward. He is a member of the Self-Defense Forces and Soldier's junior. He joined the Self-Defense Forces after being recruited by the Self-Defense Forces Regional Liaison to avoid a juvenile reformatory for stealing. He originally could not swim, but overcame his weakness and swimming difficulties by working with Soldier during the Kano River typhoon rescue operation. After that, he has been seen fulfilling his promise to Bro and seeing Mario off for the U.S. in place of Soldier, who is in prison.

Shōnan Special Reformatory

Ishihara (石原)

Voiced by: Kōji Ishii

Appears in chapters 1, 2, and 4. He is a jailer at the Shōnan Special Reformatory.

Since Bro knows the truth about a certain incident, he teams up with Sasaki to prevent Bro's release from prison by any means necessary, ultimately leading to the deaths of his colleague Kumagai and Bro.

He is a Philopon addict, and as he confronts Bro, his addiction gradually progresses to the point of mental instability, and as a result, by chapter 2, he has deteriorated so much both physically and mentally that he cannot tell Bro and Mario apart, and has become disabled.

Gisuke Sasaki (佐々木 義助, Sasaki Gisuke)

Voiced by: Takaya Hashi

Appears in chapters 1, 2, and 4. He is a commissioned doctor at the reformatory. When Bro finds out the truth and evidence of an incident he caused, he abuses him along with Ishihara in order to hide it and keep it in the dark. He is a pedophile, and he takes incarcerated boys to his room at night and violates them.

He later mortgages a hospital and runs for mayor. He was the most promising candidate in the mayoral election and was sure to win, but he lost the election after his scandal was exposed at a speech by the six inmates.

Kumagai (熊谷)

Voiced by: Tsuyoshi Aoki

Appears in chapter 1. Unlike Ishihara, he is a warmhearted and sympathetic person who is trusted by the seven inmates, who call him "Dr. Kumagai." He supports the seven in secret under the watchful eyes of Sasaki and Ishihara, but his actions become known to Ishihara, and he is killed in what is ostensibly treated as an accident.

Eiichi Hagino (荻野 栄一, Hagino Eiichi)

Voiced by: Kōhei Kiyasu

Appears in chapter 1. He was admitted to the Shōnan Special Reformatory for robbery.

He was made a plaything for Sasaki, who promised him a reduced sentence in exchange, which he later reneged on, causing him to fall into despair. He entrusted Bro with the truth of the incident and the evidence, and committed suicide in 1954.

Manga

Rainbow is written by George Abe and illustrated by Masasumi Kakizaki. Abe wrote the series based on his own experience in prison.^[2] The manga started its serialization in Shogakukan's seinen manga magazine Weekly Young Sunday on November 21, 2002.^{[lower-alpha 1]} After Weekly Young Sunday ceased its publication on July 31, 2008,^[6] the series was transferred to Weekly Big Comic Spirits, starting on June 15, 2009.^[7][8] The series finished on January 4, 2010.^[9] Shogakukan collected its chapters in twenty-two tankōbon volumes, released from April 5, 2003, to February 27, 2010.^[10][11]

Anime

An anime television series adaptation was produced by Nippon TV, VAP, and animation studio Madhouse, directed by Hiroshi Kōjina, with Hideo Takayashiki handling series composition, Ai Kikuchi designing the characters and Yū Takami composing the music. The series ran for 26 episodes on Nippon TV from April 6 to September 28, 2010.^[12] The opening theme is "We're Not Alone," performed by Coldrain, and the ending theme is "A Far-Off Distance," performed by Galneryus.^[13]

The series was simulcast by Funimation with English subtitles in 2010.^[14] In October 2023, Discotek Media announced that they had acquired the series. It is scheduled to be released on Blu-ray, including Japanese audio with English subtitles, in 2024.^[15]