VS. Special Fire Force Company 5 arc

The 5th Brigade arc is the second story arc of the Fire Brigade of Flames series. It follows the events after the Fire Officer Newcomer Tournament, which include the parole of the ex-criminal Setsuo Miyamoto who turns into a sentient Flame Human and causes trouble in the urban city of Tokyo, while the 5th Special Fire Brigade interfere with Shinra's actions to take down the Flame Human and causes rivalry between the two brigades. The arc takes place between Chapter #09 to present.

The Sentient Flame Human
Akitaru gets approached by Shinra and the two begin talking about the origin of the Special Fire Brigades and how the 1st, 2nd and 5th brigades came to be. Akitaru tells him that each brigade has their own ulterior motives and are potentially hiding something on their end, regarding knowledge on Flame Humans and the Phenomenon. He also tells Shinra the purpose of the 8th Special Fire Brigade. Shinra asks Akitaru to allow him in helping with the investigation, but the two are interrupted by Takehisa, who comes by to report the results of the research on the powdery substance Joker was using in the fray. Meanwhile, Joker discusses the events of the Fire Officer Newcomer Tournament and reports on the 8th Special Fire Brigade with his associate. Maki sends off Shinra and Arthur to rescue Mamoru, who was seen stuck in a tree, and when the two Fire Officers do, Shinra is told that the trial for the release of the convict, Setsuo Miyamoto, is going to be held. In the courtroom, the prisoner gets paroled due to him being insane and, as soon as he gets out, the man turns into a Flame Human. The 8th Brigade moves out to take care of the situation.

Setsuo uses his new powers to kill innocent people and the judge in the courthouse. In the meantime, Arthur and Shinra notice the Matchbox passing through. From inside the vehicle, Takehisa scolds the two Fire Officers and promises to punish them. Shinra uses his ability to fly and catch up to the moving vehicle, with Arthur jumping on Shinra to grab a lift. Takehisa informs the two that a Flame Human was spotted in the courthouse and tells them to go on ahead. In the courthouse, Setsuo grabs his lawyer, telling the man that his life now belongs to the Flame Human. From out of nowhere, Arthur and Shinra attack Setsuo. The Flame Human targets an innocent girl in the area for his attack, but she is saved by Maki. Realising his predicament, Setsuo tries to surrender, hoping that his life would be spared, but is shot at by Takehisa. In retaliation, he uses his flames to distract the man, allowing himself to run away. Setsuo then promises the brigade that he will kill innocent people just like Special Fire Brigades kill Flame Humans. In order to deal with the threat, Takehisa asks Shinra to catch up to the Flame Human using his ability and dispose of him, which Shinra promises to do in order to save the lives of innocent people.

5th Brigade VS. 8th Brigade
Setsuo arrives to a crowded location and targets a young boy for his next attack, however, when the Flame Human begins approaching his prey, Shinra jumps in to save the innocent person, kicking Setsuo away with the help of his Ignition Ability. Setsuo, however, argues that he has the right to kill people as he has saved many lives, and so he picks up a vehicle and throws it at innocent bystanders, but Shinra manages to jump in and kick the car away, much to the shock and horror of the Flame Human. In the meantime, the 5th Special Fire Brigade are seen watching the fight between the two from the sidelines. Shinra begins praying for Setsuo's soul as he walks towards him, with the dedication to end the man's life, however, the Flame Human requests the luxury of having a sister pray for his soul. Using such a plea as a distraction, Setsuo attempts to attack Shinra from behind the boy's back, but the Fire Officer quickly reacts to such an attempt and cuts off one of the Flame Human's arms with a fiery kick. As Shinra prepares to end Setsuo's life for the second time, Princess Hibana jumps in to protect the Flame Human from further jeopardy.