|“||A bat ain't somethin' to hit people with! It's for givin' hopes and dreams to people!.||”|
–Zenji Banba, Volume 2, 2nd Inning
Zenji Banba (馬場善治, Banba Zenji) is a private detective who runs his own detective office in Hakata and works closely with police detective Shigematsu and the informant Enokida. He is the second and current Niwaka Samurai, an infamous hitman of hitmen in the Fukuoka area, and a member of the Hakata Tonkotsu Ramens baseball team.
Banba is described as a tall, lean man usually donning a white sweater with old jeans. The novels describe him as having brown eyes and unkempt, black hair, though illustrations show him with dark brown hair. Despite his noted height, he is usually hunched over.
Banba has a gentle and laid-back personality. He does not care much for his appearance or the cleanliness of his residence, much to his roommate's annoyance. He is mostly clueless about technology and is often used by Enokida to test new gadgets and devices. He is usually patient and understanding in most scenarios, but when it comes to baseball he can be critical and overbearing, especially to the novice of their team, Xianming Lin.
With his mother dying shortly after giving birth to him, Zenji Banba was raised single-handedly by his adoptive father, Kazuyoshi Banba. Banba had a normal and peaceful childhood until one day during high school he arrived home to find an unknown man stab his father. Having just came back from his baseball club activities, Banba attempted to attack the intruder with a baseball bat on hand only for it to be taken from him and used on him instead. He lost consciousness, and by the time he woke up another man wearing a Niwaka mask knocked out his attacker before calling the ambulance to get Banba medical treatment.
Banba awoke later and was informed that while he managed to survive almost certain death his father did not make it. He asked one of the police detectives who frequently visited him for questioning, Shigematsu, about the man wearing the Niwaka mask he saw. Determined to find the man, Banba dropped out of school and started working at a host club in the Nakasu area, where the man in question was noted to shown up on occasion. Once he found him, Banba demanded the Niwaka Samurai at the time - Masataka - to teach him how to kill. Masataka agreed, and Banba spent the next few years being trained under his wing.
Mayor Harada Scandal ArcEdit
In Kego Park, Banba meets with Shigematsu, who informs him of the recent death of his colleague, Takeda. While his death is officially ruled a suicide, the two conclude he was most likely killed for investigating Mayor Harada and the people he was connected to. After Shigematsu gives Banba a photo sent to him by Takeda, he asks him to figure out the circumstances behind the detective's death. The photo shows the mayor in the company of two unknown men and a woman. Spotting the women in the park with the mayor, Banba pops a child's balloon to gauge her reaction. Suspecting her to be a killer, Banba decides to consult the informant, Enokida.
He learns that the woman with the mayor is Reiko Asakura, an assassin and former Murder, Inc. employee who specializes in killing people with poison. Banba points out that it is unlikely she was responsible for Takeda's death and asks Enokida if he can dig up any information on anyone who specializes in strangulation. With this, Enokida swiftly pulls information on another former Murder, Inc. employee, Hisashi Ivanov. Before Banba leaves, Enokida gives him a GPS-equipped redback spider model listening device.
On his way home, Banba runs into Yamato and ends up questioning him about the people pictured with the mayor. Yamato recognizes one of the men in the photo as Takashi, an employee of a club called Miroir, so Banba heads there in an attempt to find out more. However, when questioned, the manager claims to not even remember if the mayor had ever been there. Banba is confident he is lying and leaves knowing he succeeded in confirming their relations and catching their attention.
After updating Shigematsu on the situation, Banba returns home to find himself being greeted by an unexpected visitor - a hitman named Xianming Lin, who came in order to protect him from other hitmen the Kakyuu Association will send. He explains that while he had originally been sent to kill Banba, protecting him was his way of getting back at his employer over a disagreement. Since Banba decides to humor Lin by staying inside and out of harm's way, he gives Lin the task of going out to buy some mentaiko.
The following morning, Banba leaves the office while Lin is sleeping and meets up with Enokida in order to find out more about Lin. He returns home to find Lin, who has tied up a killer dispatched by the Kakyuu Group. After letting him go, Banba offers Lin money for information. When Lin agrees, Banba learns from him that the other man in the photo with the mayor is Zhang, a Kakyuu executive and Lin's direct superior. Lin takes the money and leaves. Later that day, Banba tracks Lin down with the listening device he had put on him earlier and arrives at the Kakyuu office shortly after Lin kills Ivanov. Banba takes Ivano'v cellphone before attaching a listening device to Ivanov's collar. He then leaves with Lin, who, due to his wounds, loses consciousness. Banba takes him back to his office.
Not long after Lin regains consciousness, Shigematsu arrives with information concerning Takuya Itou, the man suspected of murdering Qiaomei Lin. Having gathered no new information, and in agreement that Itou had nothing to do with the murder, Banba accepts Lin's request to locate Qiaomei's killer and asks for five years worth of mentaiko as payment. Enokida arrives to share his findings into the killers hired by the mayor. He shows Banba and Lin the footage from the surveillance cameras at the hotel Takuya Itou was staying at, revealing he was set up by Mayor Harada's employees, Reiko and Munakata. Enokida plays them the recording from the bug Banba planted on Ivanov's body and hear of Yusuke Harada, the likely culprit of Qiaomei's murder. Lin formulates a plan to have himself be sold to Yusuke as a woman trafficked by the Kakyuu Association in order to kill him, and he asks for Banba's and Enokida's help.
Later that evening, Banba pays a visit to Genzo, a killer agent. Genzo tells him that a request to kill both him and Lin came in from the Kakyuu Association, who have hired the Niwaka Samurai to carry out the job. Banba accepts the job, regardless that he is both the hitman and person wanted dead, and heads to Saeki's cosmetic clinic, where he makes an offer to buy a body that had just been dropped off by Jiro Tanaka. After Banba relays the events to Jiro and hears about Jiro's own case, realizing they correlated, Banba asks him to avenge Qiaomei's rape and murder and lets him know that Yusuke is the culprit. Later that day, Banba, as the Niwaka Samurai, visits the Kakyuu Association offices to accept his assignment from Zhang.
As planned, Banba meets with Lin, disguised as a Kakyuu Association broker. He gives Lin one of Enokida's listening devices and a microphone to call him in case of trouble before having Lin hide in a suitcase. Banba goes to the meeting, and the suitcase with Lin inside is transferred to a car trunk. When Lin comes face-to-face with Zhang and realizes he has been set up by Enokida, he calls Banba for help through the microphone. Banba is called by a distressed Lin for backup but ignores it, keeping up his Niwaka Samurai persona. He is ordered by Zhang to behead Lin but instead cuts down Zhang and his men, including Shinohara and Munakata, and retrieves Munakata's phone. After he releases a puzzled Lin from his bindings, he removes his mask and reveals his identity. Shortly after, Shigematsu arrives to clean up the crime scene and allows Banba and Lin to leave to confront Yusuke Harada.
Banba dons his mask again before meeting Jiro and Saitoh outside of Yusuke's apartment. He calls Reiko from Munakata's phone and introduces himself as the Niwaka Samurai, announcing that he is coming for Yusuke. When she rushes out of the door to escape, Jiro captures her and knocks her unconscious before Banba and Lin enter the apartment. The mayor's son comes out of hiding and attempts to ambush them with a gun, but before he can shoot at them, Saitoh throws a baseball at him and incapacitates him. Banba is impressed by his pitch, and before loading the unconscious Yusuke and Reiko into Jiro's waiting van, they invite Saitoh to join their grass-lot baseball team, the Hakata Tonkotsu Ramens.
Later, Banba and Lin go to a warehouse where Yusuke is bound to a chair. Banba interrogates Yusuke while Jiro records his confession, which they send to Enokida so he can edit and broadcast the confession. Banba stops Lin from beating his sister's murderer to death, and when his wounds reopen, carries him away before the avengers begin their torture.
Upon hearing that Lin has no place to go, Banba offers him a place to stay at his office. Around this time, he also convinces Lin to join their baseball team, despite Lin not knowing anything about baseball.
Niwaka Samurai Impersonator ArcEdit
A half year passes, and Banba and Lin have not improved as teammates. When they begin to fight on the field during a game, their teammates break it up. Banba attempts to offer Lin criticism and advice in the benches, resulting in the two coming to blows again and making their teammates worry about their prospects in the upcoming tournament.
At the start of July, Banba begins to wrap up his remaining jobs before he goes on hiatus for the annual Yamakasa event. He receives a client, Kumiko Izuku, and accepts her request of uncovering her husband Tadafumi's affair. Banba calls Yamato up for a favor, asking him to recommend Lin for a position as a hostess at Club Eve. During Lin's shift, he visits as a guest to check up on Lin's progress and talk with Sayuri. Afterward, he leaves the club and goes to complete an assignment as the Niwaka Samurai.
He finds his target, Yasukuni Shindou, as he makes his escape through the hotel garage. After striking down his target, he stumbles across Lin, who had been hired as Shindou's bodyguard. Lin tries to attack him out of frustration but slips and falls, not paying attention to his surroundings. Banba offers him advice, and the two return to Gen-chan, where Lin informs him that the Kakyuu Association is hunting the Niwaka Samurai and is looking to hire the infamous hitman G.G. Banba is taken aback, but Genzo confirms that G.G is retired. Banba dismisses the issue and informs Genzo he will not be taking any more jobs as the Niwaka Samurai until the Yamakasa event ends. Starting the next day, Banba only focuses on preparing for the festivities and leaves Lin to handle Kumiko's case.
On the day of the Yamakasa event, Banba is approached by Genzo, who delivers the news that Lin took a job as the Niwaka Samurai in his place and has been presumably killed. He shows the picture of the fake Lin's body, and initially believing it, Banba decides to leave the Yamakasa to meet with the person who has Lin's body. He encounters Shunsuke Saruwatari. Banba insists on seeing the body and when he does, he immediately recognizes it as a fake. Relieved, he turns to leave and head back to the Yamakasa event, but Saruwatari instigates him into a fight. They exchange a few blows until members of the Kakyuu Association appear and interrupt the fight. Surrounded, Banba surrenders and allows himself to be taken to their hideout.
Banba is brought to the torture room at the Kakyuu Association's offices where he had struck down Zhang and Munakata's group the year before. As he waits for his fate, Saruwatari busts into the hideout and kills the guards, setting him free. Saruwatari proposes a temporary truce, wanting the right to fight with the Niwaka Samurai. The two team up and fight the hoards of men attacking them, retreating to the rooftops for a standoff. Once the threat is subdued, Saruwatari and Banba resume their match. During the fight, Banba successfully hits back Saruwatari's shuriken, causing him to stumble off the rooftop. Banba manages to catch him and save his life, declaring that he won the round and promising to fight again another time.
After Saruwatari departs, Lin arrives at the rooftop and finds Banba. A surviving member of the Kakyuu Association takes a shot at Banba, and Lin warns him in time to avoid the attack. The two team up to take the man down. Afterward, Banba laments missing the Yamakasa event, and Lin offers to treat him to ramen to cheer him up.
A week later, the Tonkotsu Nine face off against a grass-lot baseball team from Kitakyushu and struggle against their underhand pitcher. When Banba goes up to bat and is narrowly hit by the pitcher's poor throw, he loses his temper and starts arguing with the pitcher. The situation escalates, resulting in the two to exchange blows, knocking their hats off and revealing their faces to each other. Banba immediately recognizes the pitcher as Shunsuke Saruwatari, the Submarine Ninja. The encounter strengthens their rivalry as both hitmen and baseball players.
Shou Wang ArcEdit
Banba goes to a batting center for practice and runs into Saruwatari. He dismisses the ninja until Saruwatari's comments on his batting provoke him, and he teases Saruwatari on his pitching in turn. When Banba returns home, Lin and Sayuri are waiting for him, and Sayuri gives him a list of Kakyuu Association members before leaving the country. Banba drags Lin to the office of Takashi Unoyama, where they pose as a lawyer and secretary in order to gain access. By using a samurai sword on display in the office, they eliminate the seven members inside and head to the apartment of Byeong-Hee Kim. A crowd of bystanders and police have formed around the building, however, and Shigematsu drags Banba and Lin a short distance away to inform them that Kim was murdered and he has been tied to mafia activity. When they hear that a shuriken was found near the body, Banba and Lin both recognize the work of the Submarine Ninja and realize that the troublesome ninja is targeting the same individuals.
Banba attends the Tonkotsu Ramens' weekly practice and helps teach Lin the team's signs. Banba pitches while Lin practices reading the signs and stealing second and advises Lin to trust in his teammates. He meets with Enokida at a ramen shop in JR Hakata City the next day, where Enokida informs him that one of the spies he had planted in the Kakyuu Association has been killed and the other is unable to move freely, preventing him from discovering the locations of the executives who have gone into hiding. The one moving openly in the interest of the organization is a man named Suzuki, who Banba decides to tail. Enokida also informs him that a man named Yang has shown up asking about Lin, but at that moment, the feed from the tracking device placed on Yang is switched off. Banba is worried about Lin, who has been distracted and lost in thought lately.
Banba struggles to wake Lin from a nightmare the next day, but Lin pushes him aside. He hears that Suzuki is on the move and heads to Hakata Pier, where he jumps in a fishing boat to watch from the water. He witnesses Feilang slaughtering the Shou Wang subordinates and Saruwatari showing up to fight him. When Saruwatari throws himself into the sea to dodge a bullet and begins drowning, Banba pulls him into the fishing boat, and pushes him in the water again when he refuses to talk. Saruwatari pulls Banba overboard in turn, and after the two fight in the water for a bit, they both climb in the boat and decide to share information.
When Banba returns home, Lin has disappeared and left only a note behind. Banda calls Enokida, who denies knowing anything, even though he is sitting at a coffee shop with Lin at that moment. Banba moves forward with his current case and bugs the private room in the restaurant in Nakasu where Ruixi Li and Suzuki are meeting with Feilang. He listens as Li is poisoned and removed from the room and Feilang discovers and destroys one of the listening devices he had planted inside. The conversation ends and Banba is not in a position to get close to Li, so he returns home, where he is shocked to find a report in the news about the separate stabbings of two men named Noriaki Hayashi, a name spelled with the same kanji as Lin's. Worried, he calls Enokida to look into the murders.
Banba visits Gen-chan later that evening for dinner and a meeting with Enokida, where the informant fills him in on Feilang. As they are talking, Lin calls for help, and as a precaution, Banba asks Genzo for help before departing. Not to be left out, Enokida volunteers his services. Banba rushes to find Lin but is shot in the torso by Feilang the moment they spot each other. He passes out and the two men are brought to the Kakyuu Association headquarters, where they are attended to by an underground doctor and imprisoned. When they come to, Banba is trying to provide Genzo and Enokida with as much information as possible through his earpiece while remaining inconspicuous. Feilang enters the room with a large bag of weapons, which he begins throwing through the cell bars. He orders the two men inside to fight to the death, but neither Lin nor Banba move a muscle. When Feilang decides that Banba will have to die and points a poison-tipped arrow at him, Banba picks up a baseball bat and gives Lin the Ramens' team sign to run. He returns the poisoned arrow, striking down a Kakyuu Group subordinate, and throws a short sword at Feilang, piercing him in the leg. Feilang is carried out by the remaining subordinate, and the room is sealed behind them. As poisoned gas begins to fill the room from vents in the ceiling, the fireworks begin in Ohori Park and Banba and Genzo count down the timer of the explosives placed around the room's exterior.
After a wall of the room is blown away, Banba and Lin exit into the courtyard, where Genzo holds off the few subordinates attracted by the noise. As they break back into the manor to search for Feilang, Banba offers to kill Feilang, worried about Lin's ability to strike down his old friend. At the worst possible timing, the Submarine Ninja appears with the same target in mind. Banba stays to hold him off while Lin pursues Feilang. His wound reopens during their fight, severely limiting his abilities, and he attacks quickly in the hopes of finishing their fight before he becomes unable to move. Saruwatari notices his urgency and backs off, throwing shuriken at him instead. Though Banba attempts to hit it back to him, the shuriken is thrown in a curving pitch and lodges in Banba's thigh instead. He falls down and is met with the ninja's sword at his throat. Banba acknowledges his defeat, and Saruwatari, content with his victory, leaves for Kokura. Banba rushes off in search of Lin, finding him on the street outside standing over Feilang's body. They two help each other back to Genzo's car with the shuriken still stuck in Banba's leg. The next day, Banba is eating ramen when Lin wakes up, and Banba welcomes him home.
A month after the end of the story, Banba and Lin meet other members of the Tonkotsu Nine at Bar Babylon. Banba approves of Lin's decision to continue crossdressing, stating that Lin looks good in everything. Dressed in jinbei and yukata, the teammates head to a fireworks festival together.
Banba is in a depressive slump after his favorite pro baseball team's seventh consecutive defeat, but Lin manages to drag him to Genzo's stand. Barely in the mood for ramen, he asks Genzo for work as a distraction and accepts the leftover job after Lin takes first pick.
Banba's job takes him to meet with a former yakuza-turned Italian restaurant owner whose restaurant has been the target of hundreds of negative reviews from one company employee. Despite the employee being reprimanded by his superior at work, the posts have continued and business at the restaurant has taken a hit. Wanting to save his restaurant, the owner gives Banba the name of his target, Yusuke Aoyagi. Banba arrives at Aoyagi's apartment that evening as the Niwaka Samurai and enters from the balcony window. He is shocked to find Aoyagi hanging from the ceiling by a rope around his neck. While looking around the room, he finds Aoyagi's suicide note, a profession of his innocence.
Though his job is technically over, Aoyagi's suicide note bothers Banba, and he meets with Shigematsu the next day to confirm the suicide as genuine and learn more about the victim. The case reminds him of Saitoh's recent arrest, and after returning home to think it over, Yagi visits as a client. Minutes later, Enokida arrives, only to flee after spotting Yagi. Banba is initially shocked by Yagi's leap from the third-floor window, but he had already suspected that Enokida had a privileged upbringing is only concerned with the possibility that Enokida's family's searching for him might deprive the Ramens of their center fielder.
That evening, Banba again visits Gen-chan to inform Genzo of the outcome of the Aoyagi job and his suspicions of Aoyagi being framed. Genzo gives him the job of eliminating Manabu Kuroiwa, a troublesome hacker. Banba runs into Enokida and Lin in Kuroiwa's apartment, and when the three check the apartment's surveillance footage, they find evidence of his abduction. As Enokida takes the footage the victim's smartphone for analysis, Lin tasks Banba with questioning the homeless about disappearances.
Banba begins asking homeless people in nearby public facilities, and after numerous unhelpful replies, he finds a lead. A man sleeping in a park points out a pile of cardboard and vinyl sheeting left behind by an older homeless man who has gone missing. The man tells Banba how he came to be living on the streets as a result of the Cracker, a killer in Fukuoka who eliminates his victims socially by spreading lies about them or framing them, destroying their lives, and Banba realizes that his jobs have led him toward a dangerous hitman. Shortly after leaving the park, he receives a call from Lin and rushes to find Enokida near the Gate's Building, narrowly saving him from a hitman. When Enokida realizes that their location is being tracked remotely, he leaves Banba with the promise to be in touch when he needs help.
Banba returns to the office, where he and Lin watch Enokida's location via Undergroundjobs.com and wait for him to make contact. They receive simultaneous texts soon after, and by combining the messages, Banba interprets Enokida's hidden message and contacts Yamato. When Yamato brings them Enokida's wallet, they find a script written by Enokida inside. Following his directions, Banba waits until Lin has visited the restaurant and calls Enokida to confirm passage on a ship leaving Fukuoka. He arrives at the restaurant a while later to meet up with Enokida, who is now dressed in Lin's clothes. The two follow Lin's transmitter and arrive at Irasawa's house, where Lin is waiting in the garage with a beaten and bloodied Irasawa. The three help Martínez move the boxer to the avengers' warehouse and wait throughout the five-hour torture session.
The following afternoon, Banba visits the PC Doctor's Studio. Silently entering the locked back room, he witnesses Siva making an upsetting post from a celebrity's hacked social media post. When Siva notices him, he attempts to fight back by throwing his monitor at Banba, but having finally caught up with his target, Banba finishes his assignment and stabs Siva through the chest.
- A native to the area, Banba is noted to speak the local Hakata dialect.
- His favorite foods are Hakata tonkotsu ramen and mentaiko (another Hakata specialty).
- He is a huge baseball fan and his favorite team is the local Fukuoka Hawks. He uses their theme, "Iza Yuke Wakataka Gundan" (いざゆけ若鷹軍団), as his ringtone.
- He owns a Mini Cooper described in the light novel as red with white lines. It is shown as blue in the first anime trailer but is red in the anime itself.
- He knows little about technology and owns an older cell phone model instead of a smartphone.