Joker

is a man who knows the truth of Shinra's past, and is a wanted criminal who poses a major threat against the Special Fire Brigade.

Appearance
Joker is a tall young man with long, black, stringy hair that falls below his neck, and a spiral-shaped iris in his right eye. Joker's outfit resembles that of a cowboy. It consists of a black top-hat, a patterned black bandanna across the left side of his face which covers his left eye, an old-fashioned shirt with a black waistcoat, as well as alternating white and black trousers and shoes. He is commonly seen smoking a cigarette, and usually carries a menacing grin on his face. Later on, Joker is seen wearing dark jumper with two hearts on the left side of his chest.

Personality
Joker is a mischievous man who works behind the scenes to accomplish his goals. Shown to be very sneaky and somewhat intelligent, he always tries to play the cards his own way, going as far as involving innocent people. Joker can be manipulative in the sense that he will use other people's interests as a way of unconsciously leading them to where he wants. In some respects, Joker is lackadaisical and can get caught up in the moment, where he forgets his original goal. He is considerably a sadistic individual who enjoys hurting people and toying with their emotions. He's also willing to offer information to his opponents, in exchange for entertainment. He is charismatic and knows how to sway people to join his cause. Joker also has high expectations for Shinra and wants him to become a "Devil" to uncover the truth of his past, potentially hidden by the Special Fire Brigades.

Physical Prowess
He is skilled in hand-to-hand combat, as demonstrated by effortlessly dodging most of Shinra's fiery kicks with ease, as well as keeping the boy on his toes the entire time they fought. Joker is also fast, capable of catching up to Shinra, who was using his ability to accelerate himself. In the midst of battle, he can notice movement as simple as change in trajectory, making him observant and sensitive to his surroundings.

Ignition Ability
Joker has adapted to the Human Body Ignition Phenomenon by becoming a Second Generation and was granted the ability to manipulate flames. He uses the his lit cigarette to create various shapes in the form of letters, suit of cards or card-shaped projectiles. With the use of his ability as a Second Generation, he also uses powder, made of Flame Human ashes, that instantaneously cause explosions or burst things into flames at command, as an offensive maneuver.

Introduction arc
After the 8th Special Fire Brigade finishes their assignment, Joker uses a powder-like substance he received earlier from an associate to force the building's ceiling that the 8th were in to collapse, but the brigade fortunately manages to escape unscathed. Joker later intrudes on the Fire Officer Newcomer Tournament, where he assaults two members of an unspecified brigade in the building. He gets spotted by Shinra, which leads him to taunt the boy about his past and truth behind his family's death. When the man threatens to kill the innocent bystanders, Shinra attacks him with a barrage of kicks, but Joker manages to dodge them all with relative ease.

Soon after, he then reaches into his pocket to reveal the same powdery-substance as before, and unknowingly to Shinra, uses it to cause an explosion which he is blown back by, which Joker uses as a diversion to head in for an attack. The man throws card-shaped projectiles, injuring Shinra. Without giving Shinra moment to react, he closes in on him and elbows him in the chin. As Shinra is on one knee unable to stand, Joker steps up to him, wondering whether he should kill Shinra. Shinra puts on a sadistical smile, realising his death may be upon him.

Taking notice of this unusual expression, Joker is impressed with how he is able to smile under such circumstances, leading him to reveal to Shinra as a reward that Shō is still alive. Joker informs Shinra that the Special Fire Brigades are potentially hiding something from him, however, Shinra attacks him, but does not manage to connect a single kick. When Tamaki and Arthur show up, Joker attempts to get rid of the two, but to no avail. He then uses an explosion as a diversion and flees, encouraging Shinra to show his dedication to becoming a hero by saving everyone and offering him the chance to join his cause instead of the Special Fire Brigade. The next day, Joker becomes a wanted criminal and discusses the events of the tournament and the 8th Special Fire Brigade with his associate.

Tracking the Preacher arc
Joker later appears in an unknown location, listening in on the conference of the Battalion Commanders via a device. After the conference when the brigades disperse, Joker surprises Shinra by greeting him in the middle of an alley while he was alone, insisting that instead of fighting, he'd like to reveal some information to him as a reward for coming so far. He then speaks about Shō Kusakabe, exposing his alliance with the preacher.