Inui Banjin is a camouflage-wearing, hand-to-hand fighter who mirrors Sanosuke in intelligence (lacking-in). He is the student of Tatsumi, the leader of the ninja group that tried to kill Hitokiri Battōsai. As Tatsumi was killed by Battōsai, Inui claims to join Enishi's Jinchū campaign for that reason, but he is actually using his master's death as an excuse to fight and prove how powerful he is. In reality, he cares nothing for his master whom he thinks of as a mere loser.
Inui wears military-styled pants with crossed shoulder straps with a matching headband. He wears black combat boots and a belt with a number of cases. He finally wears his gauntlets, which changed design before his humilating defeat.
While he is somewhat skilled in offense, his fighting prowess is utterly overshadowed by his immense hubris, and he has a temper to match. Though being armed with steel armored plates appeared to give him the advantage against Sanosuke (who was rendered unable to use the Futae no Kiwami attack after fighting Shishio), trying to obtain a complete victory by taking Sanosuke's attack head-on did him in, and even his own comrades think little of his intelligence, as his stupidity is virtually unmatched.
Because of his obnoxious, egotistical and boastful personality, he is thought of as an immature buffoon even by his own peers, and the relationship he had with his old master Tatsumi is implied to have been stale as well, as he openly mocks him for losing against the Battosai despite his death being mostly caused by Yukishiro Tomoe.
Inui wears gauntlets on his wrists called tekkō that, according to him, can deflect any attack, even bullets, due to the angling design of the gauntlets, despite their thinness. He relies on them for defense to compensate for the fact that he cannot take damage well. Later, Enishi gave Inui a new pair of gauntlets, even more powerful than the previous, when Sano busted a fragment of the first one. Inui is skilled in Jutsushiki Muteki-ryū, which is an amalgamation of various styles of martial arts. Its techniques include Gōfubaku (Explosive Roaring Axe), where he hits the opponent with the inside of his bent arm, Raijin Guruma (Thunder God Wheel), where Inui spins as he descends from the air, then hits his target with top parts of his arms, and Ashura Sai (Asura Destroyer), where he stomps on his opponent’s shoulder, flips into the air above them, then grabs their neck, strangles them, and throws them over him. He likes to boast about being invincible and undefeated, but Sano figures out that Banjin is full of himself from wearing the tekkō and that he only fights people weaker than him.
Joining the JinchuEdit
Inui was the student of Tatsumi, leader of a group of ninjas that tried to assassinate Himura Kenshin. After Tatsumi was killed by Kenshin, Inui used this as an excuse to join Enishi’s Jinchu against the Battosai. However he didn’t care about avenging Tatsumi at all, thinking of his master as a loser for being beaten.
Assault on Maekawa DojoEdit
After Enishi began gathering his allies to begin Jinchu against Kenshin, Inui arrived at the mansion in Yokohama Enishi had rented the same time as Otowa Hyōko. Once Enishi introduced the two to Gein and Kujiranami Hyōgo, he noted only one of them remained. Inui said a man who couldn’t show up on time couldn’t be trusted and the five of them were enough. However the last of them, Yatsume Mumyōi, revealed he was there, speaking to them all from the room above them. He said it was nice to meet them and Inui demanded that he come down, but Yatsume replied he didn’t want to reveal his appearance. Enishi interrupted, explaining that the Battosai was now living under the name Kenshin, and killing him now wouldn’t be revenge. He went on to say that they had to corner him and make him recognize his crimes, then they would disband and whoever got to him first could finish him. Inui asked if that meant the strongest would get to finish him and Enishi went on to explain the plan. Inui then left with Otowa and Kujiranami, before he and Otowa went to Tokyo by train.
Upon arriving, Inui noted how it only took 54 minutes and was raring to go, but Otowa asked if he knew where to go, which he didn’t. The assassin showed Inui where they were both supposed to go on a map before they split up to carry out a two point strike. Inui went to Maekawa Dojo, where he brutally beat down everyone there, before the police showed up to stop him. He told them to attack since he could go for a lot more and asked if they thought he was finished because he was surrounded. However Sagara Sanosuke showed up, saying Inui was finished, but he just found the comment amusing and asked Sanosuke if he was a concerned neighbor. Sanosuke introduced himself, saying he was a man with tighter ties to Kenshin than anyone present and Inui said he’d have to treat Sanosuke even more nicely than the others. Inui attacked, stepping on the students he’d beaten down as he did so before kicking Sanosuke outside and asked him what was wrong as he landed, saying he’d barely started. Inui continued attacking and eventually left Sanosuke on the ground, before asking him if he was finished already.
However, Sanosuke merely responds that to hit Inui, he’d have to break his gauntlets and Inui complimented him on figuring that out. He then asked Sanosuke if he could do that, since they were designed to stop any blow. Inui went on to say the gauntlets worked with a martial arts style that conquered all styles past and present, Jutsu Shiki Muteki-Ryu. Inui said that he’d never been defeated while wearing his gauntlets and revealed his master died against Kenshin using Jutsui Shiki Muteki-Ryu. Sanosuke asked Inui if he targeted the former Battosai because of his master, but he just replied that he couldn’t have people thinking he was a loser because his master was. Inui said that nothing in life mattered but victory and he had no sympathy for anyone who lost, not even his master and he always faced forward. Sanosuke said he was relieved to hear that, because if Inui was driven by real grief, he’d think it was right to let him fight Kenshin. He then goes on to say a fight-fiend using his master as an excuse didn’t deserve to die by any code, before attacking with Mastery of Two Layers.
Inui blocked with one of his gauntlets, but it was still broken, much to his shock and Sanosuke said there was nothing his hand couldn’t crush. However his hand began bleeding due to the fact it had already been injured and Inui found the police training their guns on him. He managed to block the bullets, before asking Sanosuke how he couldn’t break his fist, when he punched his gauntlets so hard. Sanosuke just replied that the one he broke wasn’t invulnerable anymore and Inui was about to attack him again. However Gein showed up in his Iwanbo suit and told Inui to go back since it was time for Jinchu. Inui told him to get lost, since the victor hadn’t been decided yet, but Gein said he’d go even if Inui didn’t yell at him. As he leapt away, the puppet master told Inui unless he wanted to be caught in the middle of it, he should leave. Realizing he had no choice, (since Gein had left a bomb in his Iwanbo suit) Inui told Sanosuke he’d end it for today and he should be grateful for this brief prolonging of his life. Sanosuke replied it had to be disappointing since Inui missed his precious victory. Severely annoyed, Inui told him he should remember his face and if there was a next time, he would beat Sanosuke to death, before leaving with Gein.
Attack on Kamiya DojoEdit
Inui went back to the mansion with the others involved in the Jinchu and they were told by Enishi that they would attack the Kamiya dojo in ten days. While the others weren’t as onboard with the delay, Inui said he didn’t mind since he didn’t like making small moves. After Enishi explained that he was sending for his men from Shanghai, which was why he was waiting ten days, Inui (as well as Kujiranami and Otowa) thought that in ten days, Kenhin’s head would be his. As the day finally arrived, Enishi presented Inui and the others with new weapons with Inui receiving Neo-Invulnerable Gauntlets. They proceeded to Kamiya Dojo, arriving via hot air-balloon and Inui declared it was quite showy. After Kujiranami attacked Kenshin and was defeated, Inui and Otowa leapt into the battle with Inui using Raijin Guruma to smash the gate to the dojo as he landed. However Yahiko noted Inui seemed to be lacking in brains and Kaoru agreed, since using the move was pointless, much to Inui’s irritation.
Inui then declared he’d defeat Kenshin, but first he’d take on Sanosuke and, noticing his broken zanbato, said he didn’t care about his weapon. Inui said no matter what Sanosuke came at him with, he’d give him new appreciation for his gauntlets before the two threw themselves at each other. Sanosuke swung it at Inui and shattered his first pair of gauntlets (losing his weapon in the process), but he hid a more powerful pair and counterattacked, saying his gauntlets had improved shape and performance. He then asked Sanosuke how he felt now, but he responded that he was burning inside from letting his Zanbato die against a fool. Inui told him to shut up, before he started punching Sanosuke and after Gein mobilized Iwanbo Savage Mode, Inui decided he couldn’t waste any more time. However Sanosuke punched him in the face and said he didn’t remember giving Inui the luxury of time. They started arguing, eventually resuming their fight and later watched Kenshin use his Amakakeru Ryu No Hirameki on Gein’s Iwanbo suit. Inui noted that the move was interesting and told the former Battosai he’d be his opponent soon as he walked into the dojo to get his wounds healed. Sanosuke noted Inui seemed irritated, but he just told Sanosuke to shut up and to hurry up and die, since he had to keep moving. Sanosuke then kicked him in the face and asked Inui if he still thought he was going to fight Kenshin.
Enraged, Inui attacked, telling Sanosuke to look who was talking with his face drenched in blood, but Sanosuke dodged his fist and punched him, saying he was no opponent worthy of Kenshin's attention. Sanosuke told him to give up on fighting Kenshin, since he was way beyond Inui, to which Inui responds that Sanosuke was one to talk. Inui then declared that he would show him who was out of whose league with his Neo-Invulnerable Gauntlets and they attacked each other. They managed to counter each others blows and Sanosuke asked if he thought his gauntlets would work forever. Inui said Muteki-Ryu wasn’t so simple and used Gofubaku, slamming Sanosuke into a wall. Inui then said Muteki-Ryu made his whole body a weapon, but Sanosuke said it didn’t hurt to which Inui responds that this is why numbskulls were hard to deal with.
He then thinks to himself that if even Gofubaku didn’t take care of him, simply hitting him wouldn’t. Sanosuke said he wouldn’t give Inui the chance to strike and they attacked each other again, and Inui uses Ashura Sai, which sends Sanosuke through a wall. Inui looked over at Kenshin and said Muteki-Ryu brought together the best of all martial arts in the world. The former Battosai just told Inui he was in the middle of a fight and he realized Sanosuke was still going. However he was breathing heavily and Inui said even numbskulls were vulnerable in the neck. He explained Gofubaku and Ashura Sai gave four types of wounds from the strike - strangle, crush, and throw - and there was no way he’d be fine. Inui declared one more hit and it’d be all over, but he’d have to pay back Sanosuke for destroying his previous gauntlets. Inui commanded Sanosuke to try his Mastery of Two Layers against his Neo-Invulnerable Gauntlets and held one of them up.
However Sanosuke told him he had to be quite conceited to think he could stop the Mastery of Two Layers with one arm. He went on to tell Inui that “mastered” or “mastery” wasn’t something he could claim lightly and he should tone down his stupidity and conceit. Sanosuke told Inui that he should prepare for Mastery of Two Layers and an angered Inui told him he had enough of his big talk. Inui said he could finish Sanosuke with one more hit and he should think about the situation he was in. They started to argue, but Megumi interrupted, telling Sanosuke if he used the Mastery of Two Layers with the shape his hand was in, it’d be the last time. Sanosuke said when faced with a fool that claimed to have mastered it all, he couldn’t turn back. He told Inui that he’d never risked his life for anything or fought anyone stronger than him, then used an excuse to barge in on someone else’s fight.
Enraged, Inui told Sanosuke he’d kill him and crossed his arms to block the Mastery of Two Layers, telling Sanosuke that he’d yank his head right off his neck. Sanosuke attacked with the Mastery of Two Layers, shattering Inui's gauntlets (and his own fist) and badly damaging his arms. He finally knocked Inui to the floor and asked how it felt to fight someone stronger than him. Inui just retorted that he’d kill him next time and Sanosuke told him to come anytime, but he’d never win as long as he wore his gauntlets. Sanosuke said he didn’t think he’d lose to someone who wore gauntlets to cover his weakness and told Inui to master himself in the true sense, then come back. Afterwards, Inui was arrested by the police.
In Live-action filmEdit
He is played by Genki Sudo in the live action film and instead of the Oniwabanshu, it is he and Gein who work for Takeda Kanryū, against Kenshin and Sano, with him fighting and losing to Sano, after a hard fought battle. He is shown to be a vegetarian after declining Sanosuke's offer for some chicken after they took a break in the middle of their fight.