VS. Special Fire Force Company 5 arc

The arc is the second story arc of the Fire Force manga series. It follows the confrontation between the 5th and 8th Special Fire Brigades. This arc takes place in chapters 13-20 in the manga and episodes 5-6 in the anime.

The Confrontation
After the two squads square off, both Iris and Hibana give one lasting look to each other, and they return to their headquarters. The next day, Shinra meets with Akitaru and Takehisa, and they discuss the roles of what a Fire Officer in a Special Fire Brigade represents, what their goals are, and what their personal goals are as a squad: to investigate each of the individual Special Fire Brigades as they could be hiding information about the Human Body Ignition Phenomenon. Arthur, Maki and Iris later join, and after joking around when they were supposed to be having a meeting, Takehisa shoots Shinra in the leg with a pistol to call attention to the meeting. Thinking he was in immediate danger, Shinra was found surprised when he realised no damage had been done. Takehisa explained his ability as a Second Generation, which allows him to weaken the explosion of a bullet firing from a pistol, and to use this knowledge to remember that the 8th will be facing opponents with never-before-seen and unusual abilities; to keep their wits about them. The Fire Officers and Takehisa then go up to the roof to do some training. While Maki and Arthur spar, Takehisa and Shinra discuss Hibana's background about how she became the Battalion Commander of the 5th Special Fire Brigade. As time went on, and Arthur left exhausted and easily defeated by Maki, she asks for Shinra to spar with, only to find out that he had went back downstairs at the same time Iris was performing her purifying ritual. Shinra walks by and notices Iris in just a wet towel, exciting a large grin on his face. Iris begins to cry as she reminisces about the times she was at The Holy Sol Temple with Hibana.

As Iris puts on a dressing gown, Shinra apologises for disturbing her. Seeming a bit shakier than usual, Shinra asks how she is, in which she puts on a fake smile and ensures him that she is. Shinra lays in bed thinking about Iris as she seems to be having a problem, and asks Arthur's opinion on it, but he doesn't think she's acting any different. Maki bursts through their dorm, telling them both that Iris has gone missing from the church, much to Shinra's confusion. Iris appears at the 5th Special Fire Fighting Industrial Complex wanting to speak to Hibana directly. As she's let in, she tries to tell Hibana what she is doing, referring to the illegal research on Flame Humans, is a violation of the sun god that they both worshiped at The Holy Sol Temple. Hibana doesn't listen, and instead rips off Iris' habit, exclaiming she isn't worthy of wearing it. Gripping Iris' face in her hands and with an intimidating smile, she calls Iris' position as a sister in the Special Fire Brigade trivial and simply a decoration rather than anything important in the organisation, and says that the only real thing that exists in this world are demons, comparing herself to that of one. As she suggests that they use Iris as bait for the 8th to come, Hibana hears a loud noise outside the Industrial Complex. Shinra appears and claims he is going to save Iris.

The 8th's Arrival
The rest of the 8th excluding Akitaru recklessly infiltrate the Industrial Complex by ramming and the security walls with Excalibur and the Special Armoured Fire Engine. Takehisa tells Shinra to use his Ignition Ability to get going to Iris' whereabouts. Passing through the 5th Brigade's grunts with ease due to his agility and Ignition Ability, he makes his move toward Hibana and Iris. Takehisa begins his attack on the 5th Brigade grunts by using his firearms to take them out without killing them, to which Maki remarks his mercilessness toward fighting real people in comparison to Flame Humans, to which he replies saying he joined the Special Fire Brigade to beat some sense into some of the dense people across Tokyo. Maki commenting on her desire to save people rather than fight against them, is told off by Takehisa as he reminds of her of the sucker punch she did against a man from the 5th Brigade the other day. Tōru Kishiri then appears unknowingly from a distance, spotting the two conversing. Unleashing his Backdraft Bubblish Gum, he tries to harm Takehisa in the explosion, but Maki successfully prevails and manipulates the explosion away from Takehisa and herself. As the two 8th brigadiers go into hiding, Maki is able to estimate the opponents location from inside a warehouse, allowing Takehisa to use his Bullet Speed Control and Ricochet Control to defeat Tōru. When they thought the coast was clear, the 3 Angels of the 5th appeared before them, preventing them from moving onward. Arthur, following Shinra's Devil Footprint's the whole time finds himself lost in the area. Out of nowhere, a strange-looking man from the 5th Brigade appears before him, seemingly confronting Arthur. Behind the 5th brigade member, Setsuo appears with the number 5 patched onto his head and whispering to himself killing intentions. Arthur then begins to murmur with himself, flopping his attempt to say a really cool line before preparing to fight against him. Conehead explains Setsuo's new strength due to him intaking experimental drugs. As he reveals his new weapon placed on his arm, Setsuo begins his assault on Arthur. Managing to defend successfully from Setsuo's attacks, Arthur remarks himself as a knight. Hibana, residing in a different location from the fight, asks for an update of what's going on between the two brigades, in which a 5th bodyguard informs her of the confrontation between the 3 Angels of the 5th and Hinawa, Arthur and Setsuo, and Akitaru is still no where to be found. Hibana states that she wants to find the secrets of the Human Body Ignition Phenomenon and that worms like the 8th don't deserve to know. Arthur becomes cornered while Setsuo hammers into him. Persistently trying to attack him, Arthur doesn't manage to land a hit, to which Setsuo declares that he is a weakling who stays calm even though they aren't fighting well. Arthur pauses to think and realises something has been wrong the whole time; Excalibur is held in his left-hand even though he is right-handed. As Setsuo charges up his final attack, in a flash, Arthur strikes him with Flash of Lightning, splitting the Flame Human in half, ending in a quick and unexpected defeat. Conehead looks in amazement at Arthur, and Arthur swings his sword stating he knew something was off.

Shinra vs. Hibana
Takehisa and Maki finish off the 3 Angels of the 5th and search for documents mentioning secrets behind the phenomenon. As Shinra arrives at Hibana's mansion, he gets intercepted by more members of the 3 Angels of the 5th, but he defeats them with a fiery kick. Hibana realises there is an intruder, and tells Iris to pray to her petty god. Iris reminds Hibana of the time that the sisters of The Holy Sol Temple being enveloped in flames after being struck by the phenomenon, and asking her why she acts the way she does now. Claiming to be lucky to have awakened the ability to adapt to the flames and become a Third Generation, Hibana states there are people who burn and are burned, and that she is one that burns. One step away from punching Iris, Shinra bursts through the door, asserting that the hero has arrived on the scene. Shinra thinks back to the previous encounter he had with Hibana and how he felt paralyzed on the ground, but states it won't go like that this time. Hibana stops Shinra in his tracks as he dashes forward to her, and falls to Hibana's heat fever ability. As Shinra lays on the ground baffled, Hibana explains her ability to him, revealing that she enveloped him in a layer of heat, which enlarges the blood vessels, lowering his blood pressure, therefore leaving less blood cells to travel to his brain and as a result falling to dizziness. Though struggling Shinra uses nothing but resolve and fortitude to gradually stand up, pointing out that it is nothing but his imagination that is stopping him; then claiming that he'll use his imagination to become a hero. Hibana gets serious and displays her Ignition Ability. In return, Shinra puts on an intimidating grin and claims that he'll be Hibana's eye-opener.

Hibana begins her assault on the boy with a gust of flames, and as he tries to encounter her on a close range, she knocks him back to the ground. Shinra realises and becomes annoyed that he's still dizzy from the earlier attack. Hibana points out that he'll never become a hero, and continues her attack, cutting his face in the process. Iris shouts at Hibana to stop, but she points out that if a Sun God really exists, none of this would happen, attempting to tease Iris. Iris questions Hibana on whether she thinks salvation exists, which Hibana uses her past of being one of two that survived in the burning of the temple as an example. Claiming that being saved felt amazing knowing that you aren't trash like the rest, and that the status and money you gain with a position of power itself is salvation. As well as this, at the temple, all of the nuns prayed to the Sun God daily, and despite this, Hibana was one of few that were saved from the flames even though she was not enthused or faithful about the religion while the other sisters were. Shinra begins to regain his footing and relates his case of becoming a Third Generation to Hibana's, comparing them, but Hibana continues her onslaught on him, wrapping him in a whirlwind of flames. Shinra stays strong and overcomes her attacks, as he surprises Hibana by saying he will defeat her for her own sake. Hibana, startled and confused by his words, drops her guard, allowing Shinra to use his Igntion Ability to thrust forward and land a powerful punch to her face, all the while repeating his desire to be the eye-openers for her own sake.

While Hibana is knocked out, she lays on Iris' lap and reminisces of her past with the flames. Being the only Third Generation at The Holy Sol Temple, all of the fellow Sisters were always enthused to see her display of flowers made of flames. As Iris watches timidly from a corner. Hibana spots her and welcomes her to come closer. An Elder walks over and tells Hibana to stop playing with fire as it poses a threat, but Hibana says its safe. As all the Sisters go into the chapel, Iris stops Hibana and pleads to see her fire flowers again. Hibana makes a promise that she'll show her the flowers once Iris breaks out of her shell a little more. As they walk into the chapel, they are overwhelmed by the scenery of all the Sisters burning and falling victim of the Human Body Ignition Phenomenon. Covering the eyes of a young Iris, they escaped the temple to salvage themselves. Experiencing the trauma and once thinking of the flames as a beautiful thing, Hibana changed her concept of reality into one that devoted her time into researching and experimenting on Flame Humans, eventually twisting her personality into that of a self-proclaimed demon. Years passed and Hibana ultimately left her residence with Iris to pursue her goal of discovering everything there is to know about the phenomenon and living her own life. She ended up selling her research to Haijima Heavy Industries, and by giving them what they wanted, she attained the status of Battalion Commander as well as the funding for her experiments. Hibana finally awakens, finding herself on Iris' lap. Questioning Iris' resolve to help and comfort her, Iris explains that Hibana was seen as the beautiful, smart and amazing role-model of the temple, which all the Sisters saw her as being a hero in their eyes. Hibana claims that although that may be the case, she never had someone to look up to. Shinra steps in, claiming that if she's looking for a hero, he's the man for it, to which she blushes. Iris asks Hibana if she can finally see the fire flowers again, so Hibana uses her ability create iris-shaped flowers, to which Iris bear hugs her.

The 8th and 5th Start Anew
Takehisa calls Akitaru and informs him on the situation at the Industrial Complex, much to Akitaru's shock at how quickly they finished the job. Initially meant to be pretend collaborative-combat training between the two brigades so that they have an explanation for their fued, Shinra, Hibana and Iris discuss how they are going to explain their two brigades' confrontation if it ever comes down to it, and decide to hold a dinner party with both brigades instead. Shinra alludes to Hibana's sudden cooperativeness, which Hibana feels as though she can't help it since she's fallen for his heroic nature. At the dinner party, Hibana and Akitaru start talking about the recent events. Akitaru questions her decision to share her secrets of the Human Body Ignition Phenomenon with the 8th, to which Hibana expresses hat her mind had been enlightened by none other than Shinra, to which Akitaru agrees the boy is an important member of the 8th. Hibana then reveals that since she'd experimented on various dead Flame Human bodies, she realized that some of them differentiated from each other, and so suspects that somebody is creating artificial Flame Humans, though this isn't the entire truth of the phenomenon. She goes on to assert her desire to crush the person behind this, as they may have been the ones who burned the sisters as The Holy Sol Temple. Akitaru, initially uneasy by Hibana's experimentation on dead bodies, acknowledges and states that they share the same goals. Hibana then claims that all the artificially-created Flame Humans are concentrated around the shinjuku district, which happens to be area that the jurisdiction 1st Special Fire Brigade.