Atsushi Nakajima/Synopsis

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Armed Detective Agency vs. Port Mafia Arc
Aimless and starving, Atsushi arrives in Yokohama two weeks after being kicked out of his orphanage. Although plagued by the orphanage staff's cruel words, he refuses to submit and die. Initially reluctant, he decides to steal in order to survive. He intends on waiting for the next person to pass him by the Tsurumi River's bank, only to come across a young man drowning in the river and ends up saving him.

Quickly coming to, the man is displeased with being saved. Atsushi responds with great confusion, and the man clarifies he was trying to commit suicide by drowning. However, at the same time, he wanted his suicide to go without disturbance. As Atsushi gets entangled in his attempt, the man intends on doing something in return. He hears Atsushi's stomach growl and relates to the feeling, claiming he has not eaten in a few days himself. However, the river swept up his wallet, leaving him without money.

Soon after, Atsushi meets the man's colleague, Doppo Kunikida. Eventually, the two strangers end up treating Atsushi to chazuke in exchange for saving the suicidal man's life. The man finally properly introduces himself as Osamu Dazai. During the meal, Atsushi learns Dazai and Kunikida are detectives of the gifted Armed Detective Agency.

Atsushi learns their current investigation involves a giant white tiger that Atsushi remembers as one that has been following and taunting him lately after being kicked out. After forceful persuasion via Kunikida, he reveals the tiger was the cause of severe damage to the orphanage he was kicked out of. Now, it appears the tiger followed him all the way to Yokohama.

Using reward money as a bribe, Dazai pulls Atsushi into a plan as bait to capture the tiger once and for all. However, during their wait, an agitated Atsushi is at a loss for words when met with Dazai's complete nonchalance towards the tiger's looming threat. As moonlight pours into the abandoned building, Atsushi himself transforms into the aggressive white tiger. However, Dazai uses his ability to nullify the tiger, returning Atsushi to normal.

He wakes up in a dormitory and is called by Dazai, the one who set up his lodgings. Dazai claims he is about to die, and Atsushi quickly moves to check the scene, only to be met by yet another failed suicide attempt of Dazai's. After helping him, Atsushi meets with Kunikida as well, who informs them of a mad bomber at the Agency.

At the site, a young bomber holds one of the part-time clerks hostage and demands to see the Agency's president. Dazai and Kunikida plays rock-paper-scissors to determine who tries to diffuse the situation. After losing, Kunikida approaches the man, but he recognizes Kunikida and his ability, demanding he does as he says or else the bomb detonates. At a stalemate, Dazai makes Atsushi approach the young man to take care of the situation himself.

Terrified and nervous, Atsushi ends up going on a personal rant. He understands both he and the young man have nowhere to turn to. He also urges him to try finding work or another purpose instead of harming others because of his own misfortune. His intensity disarms the young man's defenses and Kunikida subdues him with his ability, The Matchless Poet.

Relieved, Atsushi is caught off-guard by an unseen figure pushing him, making him fall on the detonation device. Panicking, Atsushi uses his own body to lessen the bomb's impact, much to Dazai's shock. The bomb, however, does not go off. The bomber stands next to Kunikida and Dazai who both comment on Atsushi's impulsiveness.

The clerk, Naomi Tanizaki, hugs the bomber who turns out to be her older brother, Jun'ichirō Tanizaki. Confused, Atsushi questions the situation, to which Dazai reveals it to be his entrance exam for the Armed Detective Agency. The Agency's director, Yukichi Fukuzawa, arrives and confirms Atsushi passing the entrance exam, though he leaves the final decision to Dazai. Atsushi notices Naomi with the prop arm that pushed him onto the fake bomb, bewildering him with the elaborate setup of the exam. Dazai retorts that, if he declines, Atsushi has to leave the dorm with nowhere else to go, giving Atsushi no other choice but to accept the job.

At Café Uzumaki, Tanizaki profusely apologizes to Atsushi for causing him so much stress. Kunikida advises Atsushi not to ruin the Agency's name, while the Tanizaki siblings introduce themselves. Atsushi asks them what they did before joining the Agency, but Dazai suggests he guess their backgrounds.

Atsushi correctly assumes Tanizaki and Naomi to be students, while he guesses Kunikida to be a former government worker. Dazai reveals that Kunikida is a former math teacher, afterwards asking Atsushi to guess his former job. Kunikida remarks that no one knows his past job, having a monetary reward for the one who guesses it right. Amazed by the large sum, Atsushi eagerly guesses, but he ultimately fails.

Tanizaki receives a call from the Agency with a request from client. Her issue is a group of dangerous men hanging around her company's building. After the explanation, Kunikida assigns the investigation as Atsushi's first mission and orders Tanizaki to accompany him; Naomi joins them as well.

Before Atsushi and the company depart, Kunikida warns him of Ryunosuke Akutagawa and the Port Mafia. Kunikida informs him that Akutagawaa has an ability solely for murder, and the Agency cannot handle him. Thus, combat against him is strictly discouraged, admitting himself to be of no match for Akutagawa.

Led by their client Higuchi, Atsushi, Tanizaki, and Naomi later find themselves in a secluded alley. She reveals herself as a Port Mafia member, specifically Akutagawa's subordinate. She opens fire on the group, and the sight of Naomi's severe injuries brings Atsushi to his knees and at a loss for the situation.

His fear worsens after Akutagawa himself arrives, having attacked Tanizaki from behind. Akutagawa elaborates the Port Mafia's target is Atsushi himself, intending to claim an unknown third party's bounty on him alive, much to Atsushi's confusion. Akutagawa tells Atsushi that it is his fault for causing trouble to his comrades, bringing in flashbacks of his orphanage headmaster's harsh words condemning him for living.

After witnessing Akutagawa's ability Rashomon, Atsushi stumbles on the ground. Tanizaki, still conscious, urges him to run away. Instead, Atsushi's impulses drive him to narrowly avoid another attack, where he grabs Higuchi's gun to try and take Akutagawa down. Rashomon devours the bullets, making it impossible for Atsushi to defeat Akutagawa in this situation.

Rashomon severs Atsushi's right leg, causing him to relive another flashback of the headmaster's abuse. Here, the headmaster strikes and admonishes Atsushi for crying in pain, telling him no orphan abandoned by his own family has the right to cry. Although Atsushi knows that he has been abandoned and mistreated his whole life, he acknowledges that he has never given up regardless of the fact.

The tiger takes over and regenerates Atsushi's leg, impressing Akutagawa. When it appears Akutagawa kills him, it turns out to be one of Tanizaki's illusions. The real Atsushi attempts to ambush Akutagawa from behind, but Dazai arrives and nullifies both their abilities, rendering Atsushi unconscious.

Atsushi later awakens in the Agency's medical ward, with Kunikida seated beside him. After he remembers what happened, he immediately asks about Tanizaki and Naomi, Kunikida informs him that they are alright. When the two begin discussing the bounty on Atsushi, Kunikida explains that they will not waver and fight the mafia. However, Atsushi notices Kunikida's seeming anxiety and starts to feel guilty about putting the Agency in danger. After asking Atsushi to think how he can help, Kunikida leaves the room.

After hearing a distant explosion, Atsushi goes down the street and learns that it was done by the mafia's combat division, Black Lizard. He worries about what would happen if they attacked the Agency, so he calls Higuchi using her business card and tells her that he is quitting the Agency, urging them to find him alone.

He later bumps into Kunikida when he is leaving the office with his belongings, but he rushes back when he hears gunshots coming from the direction of the Agency, only to find that the detectives had utterly trounced the mafia's Black Lizard. As Kunikida complains how the raid being the "worst-case scenario" requires them to apologize to the neighbors, Atsushi begins to cry in relief realizing the Agency's true strength and that he has found a place to belong.

While Atsushi helps clean the office with the rest of the agency, he notices that Ranpo receives a ton of praise despite not helping and insulting the others. He is then asked to aid Ranpo on his next job, who states he does not need an assistant but someone to help him using the train.

The two of them later arrive at the murder scene and meet with officers Minoura and Sugimoto, the former stating they do not want their help. The victim, Minoura's subordinate Yamagiwa, was found in the river early in the morning with three bullet holes and no other evidence. Another body is caught in the police search net, but it turns out to be Dazai. Atsushi asks if Dazai was trying to commit suicide again, but he explains that he was not.

Shortly after Ranpo teases Sugimoto trying to get him to solve the case in 60 seconds, Atsushi thinks to himself that he probably looks that flustered most the time. He is also unimpressed by Ranpo's confident motto compared to his own. After Ranpo determines that Sugimoto is, in fact, the murderer using his ability Super Deduction, Dazai pushes Atsushi towards the armed officer, causing him to miss his shot. Atsushi then manages to disarm him and pin Sugimoto to the ground.

At the police station, Atsushi witnesses Sugimoto confess to the murder, explaining that he was working for a Diet member who ordered him to stop Yamagiwa from exposing his corruption. Ranpo later closes the case after Sugimoto reveals the location of the corruption evidence. Leaving the station, Dazai explains to Atsushi that Ranpo's Super Deduction is not an ability and merely solves crimes with his own intellect. Atsushi then realizes why Ranpo is never admonished despite his attitude.

In the morning, Atsushi is worried that Dazai is missing, but Kunikida, Ranpo, and Kenji Miyazawa think that he might be elsewhere like usual. To help appease his worry, Tanizaki volunteers to help him look for Dazai. Atsushi is glad to see him safe, but Tanizaki nervously relives Agency doctor Akiko Yosano's "treatment" and advises Atsushi never to get injured. Ranpo urges him to have a keen sense for danger, such as what will happen in ten seconds. Yosano arrives and sees no one else with Atsushi (which he thinks to be "danger"), so she asks him to accompany her for shopping.

After their spree, they ride the train back to the Agency, where they get embroiled in a bombing situation perpetrated by the mafia. They split up to find and diffuse the bombs, upon which he encounters a girl in kimono whom he encountered earlier. As he tells her about the situation, Atsushi is attacked by a katana-wielding phantom, which is the girl's ability. Launching a barrage of attacks on him, the girl introduces herself as Kyōka Izumi, a Port Mafia assassin whose ability receives instructions through her phone. Atsushi thinks he stands no chance against his opponent, but he decides to stand back up in order to save the passengers, believing that he can find his reason to live if he does so.

He partially transforms his arm into the tiger's limb and defends himself from Demon Snow. After dodging successive attacks, Atsushi demands the girl to deactivate her ability and tell him where the bomb is. She reveals the bomb strapped beneath her kimono, to which Atsushi berates her emotionlessness and apparent coldness. Through the PA system, Yosano tells Atsushi that the bomb has a detonator that can disarm the bomb. He asks Kyōka for it and presses it, but the bomb continues to count down.

The voice on the phone orders her to show the people the might of the Port Mafia by letting the bomb go off, so Kyōka pushes herself away from Atsushi and jumps off, saying her true emotions not wanting to kill anymore. Atsushi realizes her genuine feelings and, tapping into his ability, jumps off the train as well and rips the bomb off the girl, protecting her from its blast.

Kyōka is brought and treated to the Agency infirmary, while Atsushi is reprimanded by Kunikida for bringing in a wanted serial killer. As they ask her for information about the mafia, Kyōka asks them to treat her to tofu if they want her to provide them intel. As Atsushi ends up having his money thinned out due to Kyōka's appetite, she explains that she was taken in by the mafia after getting orphaned and used her ability for assassination missions. Moreover, they find out that the voice giving instructions through her phone is Akutagawa.

Outside, Kunikida asks Atsushi to hand her to the military police despite Atsushi's disapproval, knowing that she shall get capital punishment for killing 35 people. Kunikida also advises him not to let someone else beyond saving into his boat lest they drown together, but Atsushi wishes to give her another chance at life, just like how Dazai saved and took him in.

Atsushi accompanies Kyōka out to the streets and inadvertently tells her that they shall go on a date. He treats her to crêpe, gets her some gifts, and takes her throughout Yokohama. As Atsushi's wallet thins out, they soon arrive at their last stop – a police station – and she thanks him for his company. Atsushi worries that she will get executed if she proceeds, upon which he is suddenly impaled from behind by Akutagawa, who reveals to have tracked Kyōka's phone to kidnap the weretiger.

Atsushi wakes up inside a trafficking ship and gets confronted by Akutagawa, wondering where his hatred stems from. As the mafioso beats him up, Kyōka soon intervenes, but Akutagawa easily overwhelms her. Atsushi spots Kunikida below to rescue him, while Kyōka sets off a bomb nearby to sink the ship. Kunikida asks Atsushi to jump and leave the girl behind, but Atsushi firmly decides to give her a second chance and turns back to save her.

Before Akutagawa can kill Kyōka, Atsushi arrives to save her and urges the mafioso that they settle their matter at once. Akutagawa gets the upper hand with his strong offensive force, but Atsushi later retaliates with his ability. Akutagawa persistently attacks him and intermittently expresses his animosity towards him. Despite Rashomon's continuous attacks, Atsushi's regeneration enables him to survive, later berating Akutagawa for leading Kyōka down a dark path rather than directing her to another course. Atsushi soon defeats Akutagawa and plunges him towards the sea. As the ship sinks, Atsushi passes out, but Kyōka manages to get themselves aboard Kunikida's boat.

In the aftermath, Atsushi is glad that he and Kyōka survived, though he worries whether the Agency can forgive her 35 murders. To his surprise, he finds the Agency members playing with Kyōka and giving her treats, including Ranpo. Fukuzawa arrives to see the criminal in question, upon which Kyōka asks him to let her stay at the Agency. Atsushi also implores the President to help her out, which Fukuzawa accepts.

Minoura and his subordinate arrive at the office to ask for the Agency's help. He spots Kyōka and gets suspicious of her, causing Atsushi to improvise a story to get her out of apprehension. Fukuzawa simply tells the officer that she is his granddaughter, much to Atsushi's relief. Later, Atsushi and Kunikida learn about Kenji's rural town and their systems. Kunikida then tasks Atsushi to go with Kenji to investigate the recent explosion of a vehicle in town.

At the crime scene, Atsushi gets discouraged at the sight of the bizarre case, but Kenji tells him that they must first collect information. With Kenji's popularity throughout town, they soon set their eyes on a suspicious gang in question, from whom Kenji thinks they can extract the truth with their sincere questioning. Atsushi realizes how potentially effective his simple idea is. However, he gets terrified with the menacing gang, while Kenji straightforwardly asks for their involvement with the car explosion, which the gang denies. Kenji then accepts their answer and leaves with Atsushi.

Outside, Atsushi tries to point out their lies, but Kenji assures him that sincere communication will lead to understanding, which is a point that Atsushi acknowledges. On their way back, the gang corners them and “confesses” their involvement in the explosion after all. Kenji gladly thanks them, only for the gang to attack him from behind. As Atsushi panics, Kenji gets up unscathed and single-handedly defeats the entire gang with his monstrous strength. With the case closed, Atsushi calls Kunikida and expresses how too peculiar Kenji's methods are. Nonetheless, Kunikida explains to Atsushi what and how Kenji's ability works.

The Guild Arc
Atsushi wakes up and discovers that his roommate is Kyōka. At the office, Dazai advises him that it is his job to look after her, which Atsushi accepts. Dazai also informs them that the one who placed the bounty on Atsushi is a North American gifted organization known as the Guild. Tanizaki bursts in and tells them that the Guild has just arrived at their doorstep. Their leader, Francis Scott Key Fitzgerald, asks to purchase the Agency from Fukuzawa, an offer which the President rejects.

The following morning, the Agency are unsettled by the possible moves undertaken by the Guild, including how a mafia-affiliated building vanished overnight and how Kenji has turned missing after seeing them out the building. Kunikida tasks Atsushi and Tanizaki to search for Kenji, and Naomi accompanies them as well. As they look for Kenji along the streets, Atsushi and Tanizaki soon realize that Naomi has vanished.

They soon get transported to a different dimension along with other civilians by Lucy Maud Montgomery, an apprentice from the Guild. She shows the detectives their captured comrades and asks them to play with her ability, a gigantic doll-like creature named Anne. If they defeat her, Lucy promises to set their subordinates free. The other civilians flee from the room, leaving only Atsushi, Tanizaki, and a doctor behind in the dimension. As soon as Atsushi and Tanizaki accept her challenge, Anne instantly captures Tanizaki and imprisons him.

Atsushi dodges Anne's onslaughts with his ability until he gets his hand on the key to the prison room. However, it turns out to be a feint that even Lucy admits she does not know to use the key. Running out of ideas, Atsushi heads towards the exit to seek Dazai's help, but the doctor stops him and imparts some advice towards him on how to possibly defeat Lucy. As he earns back his resolve to save his comrades, Atsushi readies himself, but he gets caught by another Anne and dragged into the prison room.

Eventually, the doctor reveals to Lucy the truth: Tanizaki has projected an illusion of the door shutting close, while Atsushi actually resists getting dragged to the prison room with his tiger limbs. Atsushi also reveals having tied a ribbon on Lucy's waist earlier, then he pulls her towards him and demands she deactivate her ability. Otherwise, he will drag her together with him to the prison room. As Atsushi lets go, Lucy deactivates her ability and brings back the imprisoned people back to reality.

Atsushi tries to approach Lucy and apologizes to her, only for her to flee. Kyōka then arrives and embraces Atsushi out of worry. The doctor bids his farewell to Atsushi and imparts a final advice to him. As he and his young companion leave, Kyōka suddenly cowers out of fear, much to Atsushi's confusion and worry.

The next day, Atsushi hands Kyōka her first work for the Agency, which is to deliver an evidence to a court judge. As they arrive at the location, she is denied entrance, but she tries to resolve it using her own tactical strategy. Atsushi accompanies her to infilitrate the building, though she soon ends up stunning the judge himself, ending in a partial failure. Afterwards, Atsushi treats her to crêpe to cheer her up, later asking her why she still keeps her phone. She explains how it is special to her despite her wish never to activate her ability through it again. However, it suddenly rings, with a voice activating Demon Snow to attack Atsushi.

A woman, Kōyō Ozaki, arrives and tells Kyōka that she has arrived to bring her back to the mafia. Atsushi tells her that Kyōka shall never return to the mafia again, as she now belongs in the Agency. Atsushi activates his ability to attack the woman, only to be stabbed by another demon like Demon Snow, Golden Demon. She announces that she has to kill Atsushi and the rest of the Agency upon orders of mafia boss Ōgai Mori. Kyōka then agrees to come with her, though it turns out to be an act to catch Kōyō off-guard.

She snatches Kōyō's phone and activates Demon Snow to battle her opponent, as Kōyō keeps urging her to return to the mafia. She also reminds Kyōka how she is suited for killing, just like how Demon Snow killed her parents, much to Atsushi's surprise. In that moment, mafia reinforcements arrive to finish off Atsushi and retrieve Kyōka and Kōyō.

However, Kunikida and Kenji intervene and arrive to Atsushi's aid, inciting a war between the Agency and the mafia. Just then, two Guild members arrive alongside four more other members. Kōyō orders her men to open fire, though the Guild members easily overwhelm all the forces, including Atsushi and his subordinates.

Yosano later treats Atsushi and Kunikida. As Fukuzawa arrives to inquire about their conditions, Kunikida apologizes for failing to prevent the mishap, after which the President heads out. Atsushi and Dazai later converse with Kōyō in the infirmary, with whom Atsushi gets angry for causing Kyōka's disappearance. He transforms his arm into a tiger limb out of anger and tries to attack her, but Dazai quickly stops him by nullifying his ability. He then asks Atsushi to leave the matter to his hands.

When Kunikida updates Fukuzawa on the situation, he soon hears that the President may be under attack; Atsushi happens to pass by and suggests they help him at once. To appease his worry, Kunikida demonstrates to Atsushi how he knows the President can easily defeat his attackers.

Later, the Agency convenes at the Bankoudou Hall, where Dazai explains their strategy. To make up for their numbers, they shall split into various teams: one defense team and two offense teams. Atsushi is paired with Dazai as one offense team; Tanizaki is partnered with Kunikida as another offense team; and Fukuzawa, Ranpo, Yosano, and Kenji comprise the defense team. Dazai then finishes with their main objective which is to keep their base hidden as possible, after which Fukuzawa declares that they must survive the three-way ability war.

While awaiting Naomi's and Kirako Haruno's passenger train from the Guild's hitmen, Atsushi watches Dazai tease a dog with some treats which he also eats himself. Atsushi worries how the Agency can pull through the conflict, though Dazai thinks that they can turn the tide by about three hundred ways. However, he recognizes the mafia's most advantageous position compared to their least advantageous, considering Mori's logical and cunning calculations. Since the clerks have now let down their guard, Dazai reckons that Mori shall exploit such situation. Dazai's stomach later aches possibly from the dog treats he ate, leaving Atsushi behind. Atsushi turns to the dog and compliments Dazai despite his apparent strangeness.

As the train arrives, Naomi and Haruno introduce Atsushi to their acquaintance, who bumps themself on Atsushi and pulls up their sleeve to reveal various razor blades on their arm. Unbeknownst to him, Atsushi soon gets immersed in a curse, which turns out to be Q's ability. Seeing his companions turn hostile against him, Atsushi defends himself by using his tiger strength; he attacks Haruno and strangles Naomi in the process.

Dazai soon returns and asks him to come to his senses. As Atsushi grasps the situation, he realizes that he was the one cursed rather than the other way around. As Dazai ends the curse through his ability and Q departs through the train, Atsushi undergoes a breakdown, thinking how he does not deserve to live. Dazai slaps and lectures him not to pity himself, lest his life will be an unceasing nightmare. Dazai then announces that they must move onward with their counterattack.

Atsushi returns to the Agency and comes across Kōyō confined in the infirmary. He wonders how she can be confined if the door is unlocked, to which she clarifies that Dazai's locks are all abstract. She then correctly guesses that the lad may have come from having committed a blunder, where Atsushi tries to explain how he merely wished to protect his comrades. Kōyō tries to snap him out of it with discouragement; in the end, when asked where Dazai is, Atsushi tells her that he shall meet with a government official from the Special Division for Unusual Powers.

Kōyō sees how the Agency can find an invaluable ally in the Special Division, and Atsushi notices her seeming unconcern to the issue for a mafia executive. She threatens that she shall set out to divulge all intel she has just gathered, though she timidly informs him how she must remain silent after Dazai has made an unspeakable act to her. Calling it out as a jest, she explains how she and Dazai simply made a deal: she is to stay put in confinement while he tries to locate Kyōka, whom Kōyō notes is about to start a massacre. Recalling how she herself has never experienced Kyōka's wish to "live in the light", Kōyō implores Atsushi to help Kyōka.

Later, Atsushi awaits Dazai who has not yet returned, during which he is approached by Fitzgerald himself. Thinking how the war could end if he defeats Fitzgerald, Atsushi repetitively strikes him with his tiger strength, but Fitzgerald easily blocks his attacks. Finally, Fitzgerald overpowers and asks him to come with him, but Kyōka suddenly arrives. She quickly attacks Fitzgerald, eventually rescuing Atsushi as they escape from the scene.

Hiding from Fitzgerald, Kyōka tells Atsushi that she has called the police with a false report to arrive at their location and prevent the Guild from performing any rash actions. Recalling his conversation with Kōyō about Kyōka's dark tendencies, Atsushi wonders why Kyōka came back instead of remaining incognito and staying out of the war. She tells him that she belongs to the Agency and promises to fight for it, even if she needs to resort to her inner monstrosity. They soon approach the two policemen nearby to seek aid. As one of the two officers is notified that a young wanted serial killer in kimono is spotted in the area, he grows suspicious of Kyōka. She immediately slashes the officer out of stimulus, upon which Atsushi quickly stops her from attacking the second officer and grabs her to escape once again.

They soon encounter Fitzgerald and his companion, having anticipated the situation with the help of their tactician. As Atsushi and Kyōka are instantly and severely shot from above by Mark Twain, Fitzgerald grabs Atsushi and takes him to Moby Dick summoned by Herman. Amidst Kyōka's pleas not to take Atsushi away, Fitzgerald advises her that saving others does not suit her, to which she weeps and wonders why she is given hope if such were the case. Overwhelmed by his injuries, Atsushi is taken aboard the Guild's base and immediately departs.

Restrained before Fitzgerald, Atsushi is welcomed to Moby Dick, where he encounters Lucy, now demoted as a servant. Fitzgerald tells him that they are in search of a certain book and that Atsushi is the guidepost that can lead them to it. He reveals having kidnapped Atsushi to keep him from the oncoming incineration of Yokohama, specifically where the Agency and the mafia are based. To do so, Fitzgerald shows Q's doll, which makes Atsushi realize the danger of the plan.

As the doll soon begins its laughter, Atsushi tells Fitzgerald that the Agency shall cooperate in finding the Book, which piques Fitzgerald's interest. The latter agrees to establish a deal, but only with those who shall survive the incident. Fitzgerald then rips out the doll to activate the curse. Atsushi is locked up in a cell and tries to come up with a plan to help out. The orphanage director appears to him in a vision, dissuading him that he will only cause misfortune to others, just like how he dragged Kyōka and Lucy to their respective ordeals. In a fit of rage, Atsushi lashes out at the apparition and dissipates it.

Lucy passes by his cell and mocks him on her way to burn Q's mutilated doll. Atsushi asks her to set him free for everyone's sake, but Lucy declines. He then advises her to run, but she tells him how the Guild is the only thing she has left, unlike him who is blessed with his comrades. She shows her scarred arm that was caused by the painful time she had on the orphanage, to which Atsushi shows his identically scarred abdomen and thereby relates to her story as someone who also experienced the same unbearable acts in the past. Though he knows how they both experienced loneliness, Atsushi believes that leaving the people below to die is akin to abandoning their past selves.

Quickly bringing him to her dimension, Lucy tells Atsushi that there is no other way to stop the curse, but he states that Dazai's nullification ability can stop it if he touches the doll. Lucy tries to dissuade him due to the dangers that might befall him on the way down, but Atsushi remains steadfast in his plan, recalling a quote he once read in which regrets are a product of not doing anything. Lucy then decides to help him as Anne hands him a parachute, asking Atsushi to save her soon. As she promises to wait for his return, Atsushi jumps off the aircraft and agrees to come back for her.

On his way down, Atsushi's parachute is punctured by Twain's ability-aided sniping. As he prepares to accept his end, he eventually comes to terms with the white tiger, upon which he fully transforms into the creature and lands on the ground unscathed. Twain fires .50-caliber bullets at him, but Atsushi evades them. He then witnesses the various cursed citizens and spots a baby about to fall off some stairs. Atsushi taps into his tiger speed and successfully catches the crib, later handing the child to Michizō Tachihara nearby.

As Atsushi notices some strange objects lined up along the streets, Twain shoots a tanker truck in front of him and heavily injures him from the blast. Twain rains down a surge of shots at Atsushi and immobilizes him. As he tries to reach out to Q's doll, Dazai intervenes, nullifies the curse by touching the doll, and sets off a saturation chaff smokescreen that emanates from the strange objects, jamming Twain's infrared sensors and radar.

Atsushi and Dazai retreat to a nearby nook. Though they have stopped the cursed rampage, Dazai tells Atsushi that Q is still in the Guild's confinement and can launch the same attack how many times they want. He adds that the Special Division is currently frozen and cannot therefore collaborate with them. Recalling the quote he once read in a book – that the head may err but never the blood – Atsushi recommends a solution in fighting the Guild: forming an alliance with the Port Mafia. He soon opens a conversation with Fukuzawa and suggests his idea; in the end, the Agency and the mafia agree to hold a temporary ceasefire between them.

Later, as Ranpo and Dazai plan their next action after retrieving intel on Moby Dick, Dazai enlists Atsushi to perform a solo infiltration in Moby Dick. Dazai explains that he is a combat-type and high-speed ability user who has already been aboard the aircraft and would only be captured rather than killed if ever he gets caught, making him the most suitable choice for the mission. Though initially plagued with the orphanage director's discouragement to make him refuse, Atsushi accepts the task.

As Atsushi and Tanizaki head to the library, Atsushi learns that Kyōka is yet to become an official Agency member, since she has not yet passed an entrance exam. He worries that her cold-blooded nature might be an issue in assessing her suitability in the Agency. At the library, they are greeted by a government agent who directs them to the Night Crow, the Special Division's light attack helicopter. As they anxiously fly towards Moby Dick, Tanizaki activates Light Snow to hide their presence, allowing Atsushi to successfully enter the aircraft.

Atsushi finds the ship empty of its crew, only encountering Herman who tells him that everyone has fled before they crash Moby Dick to Yokohama. Atsushi urges Herman to deactivate his ability, but the latter has now lost control over it. Atsushi suggests to Dazai over the comms that they abort the mission, but Dazai asks him to stop the descent instead, which Atsushi acknowledges. After Herman directs him where the control terminal is, Atsushi asks him why he is left in the ship, to which Herman replies that the least he can do before Moby Dick crashes into Yokohama is to go down with it. As Atsushi sets out, he encounters Akutagawa along the hallway and clashes with him.

As Akutagawa is bent on killing Atsushi, who in turn does not understand the mafioso's reasoning, Dazai gives Atsushi some instructions on how to throw Akutagawa off from their path. Atsushi tosses his communicator with Dazai on the line; as Akutagawa catches it, Atsushi escapes.

Atsushi arrives at Fitzgerald's office, who turns out to be the one guarding the control terminal. Fitzgerald divulges their plan of dropping Moby Dick to Yokohama, afterwards offering him some pieces of advice to success and a chance to snatch the control terminal from him. However, Atsushi gets overwhelmed by Fitzgerald's strength, especially as he activates his ability. As Fitzgerald is about to rip off his limbs, Akutagawa arrives demanding to resume their fight, much to Atsushi's dismay. Akutagawa further chides his unfathomable attitude, given how Atsushi is quite oblivious to his strength yet is putting his life on the ship to fight.

Fitzgerald interjects and clobbers Akutagawa, while Atsushi soon tries to attack Fitzgerald while distracted. Atsushi spouts that true power lies in helping others who struggle in despair, but Fitzgerald quips that Atsushi himself is just like those people; having researched all about his past, Fitzgerald recounts one of Atsushi's violent near-death experiences in the orphanage. As the ship begins to descend, Akutagawa chuckles and escapes below together with Atsushi.

Akutagawa confronts Atsushi and spites his outlook of wanting to save others as if they can give him worth to live. The mafioso then loses interest in Atsushi, disappointed that he shall never get any sense of accomplishment from killing him. Atsushi wonders why he is hell-bent on performing such "accomplishment", to which Akutagawa spouts that only accomplishment can bring Dazai to recognize him. Before Atsushi can fully inquire, Fitzgerald finally locates them. Akutagawa engages Fitzgerald, while Atsushi flees towards a nearby elevator; Akutagawa follows him inside.

Akutagawa mockingly regrets having lost to someone worthless as him, but Atsushi retorts that he is nonetheless stronger than a mafioso who murders others just to flaunt his power. Though Atsushi sees how people respect him and recognize his strength, he adds how Akutagawa is the worthless one because of his mere desire of instilling fear on others. Akutagawa angrily grabs him and states how Atsushi is very lucky to have an outstanding ability that easily earned Dazai's acknowledgement, yet he dwells on his past and continues to turn a blind eye on everything he has. Before Atsushi can reply, they soon arrive at the ship's deck where Fitzgerald awaits.

As Akutagawa clads himself in a Rashōmon armor and battles Fitzgerald, Atsushi ponders on why Akutagawa thinks lowly of himself despite his formidable power, which Atsushi refuses to accept after all the murders he has committed out of his self-indulgence. Hence, heeding the tiger's strength, he partially transforms his limbs and joins the fight against Fitzgerald. He and Akutagawa bicker along the way, upon which Fitzgerald remarks on their similarity with each other. Offended that they are compared to each other, Atsushi and Akutagawa punch Fitzgerald.

Thinking that they have subdued Fitzgerald, Atsushi suggests they take the control terminal before they resume their clash. However, Fitzgerald resurfaces and spends all of his assets. Atsushi asks Akutagawa if he is foolish, to which Akutagawa acquiesces and tells him that his past has nothing to do with his current self. Atsushi then tells Akutagawa that he believes Dazai must have already acknowledged him long ago. Reactivating their abilities, the two charge at Fitzgerald. Initially overwhelmed by the fully-powered Fitzgerald, Atsushi and Akutagawa eventually combine their power and ultimately defeat the Guild leader who falls from Moby Dick.

They successfully stop the ship's descent, but it later continues to fall; Herman thinks that an outside party has hacked into the system. When Atsushi informs Dazai about the issue, Kyōka communicates with them from the UAV and plans to collide the aircraft to Moby Dick. Atsushi asks her to escape as well; she tells him that is unable to, hence thanking him instead and saying her goodbye upon accepting her fate. Akutagawa then grabs him to escape the ship with Herman while the UAV crashes into the airship.

Atsushi is distraught with Kyōka's fate, though Dazai and Fukuzawa arrive to tell him that Kyōka has passed her Agency entrance exam the moment she has decided to save Yokohama. As a result, the President's inhibiting ability that only works on his Agency subordinates has activated and allowed Kyōka to freely control her ability, enabling her to have Demon Snow cut off her shackles and escape in time. Atsushi then rushes to Kyōka and embraces her out of relief, while the other Agency members proudly look on to them from a distance.

Atsushi later accompanies Kyōka to the Agency office, where the Agency welcome their newest member. Kunikida later approaches him and Kyōka and scoldingly imparts them with various pieces of advice as their superior, especially not to tarnish the Agency's reputation and not to do anything they will regret. Yosano soon grabs and urges him to tell them what he truly wished to say, to which Kunikida complements them for a job well done in saving Yokohama.

Reflecting on Kunikida's advice, Atsushi asks for Kyōka's favor to call for Naomi and Haruno, to whom he apologizes for what he unintentionally did during the Q incident. The two clerks dismiss his worry and forgive him, but Tanizaki looms behind him and asks him what he did to his sister. Later, Atsushi notices that Dazai is absent in the party and wonders where he is.

In the anime, Atsushi and Akutagawa have a brief encounter at night after the Guild war. As Atsushi looks at the city skyline and musingly remarks that it is the city that they have been protecting, Akutagawa chides him for always talking nonsense.

The Guild Aftermath Arc
Following the battle with the Guild, Atsushi informs the drained Agency members about criminal organizations eyeing the Guild's alleged fortune. The next day, he and the others find Café Uzumaki ransacked and learn that the gang responsible were looking for them. They instantly locate the gang's hideout, where Atsushi and Kunikida take out the armed guards. When they return to the café, they are introduced to Lucy – the café's new waitress – who bashfully throws a metal box at Atsushi upon seeing him.

Plot
Atsuhi appears in his tiger form beheading the assassins attacking them one by one. After a remaining assassin speaks out and asks if his comrades are all dead, Atsushi responds, revealing himself before the assassin.

As Atsushi slowly approaches the remaining survivor, he tells him that if they were all professionals at assassinating, then the boss of Port Mafia is a professional at being assassinated. He explains every day, expert assassins go at the boss's neck with no avail, unable to pass the first floor's lobby. Atsushi asks if he is afraid of dying, saying he himself fears death and injury, so he became a reaper. To become one with death so death can't find him. Atsushi then recounts the assassin talking about a solider's way of dying, in respect, he said he would use all his power to take his life. The assassin is grateful, asking for the boy's name. To which he replies Atsushi Nakajima.

As Atsushi and Kyōka walk through the streets, Atsushi suddenly kneels down, wincing in pain with blood dripping down his neck. Revealing a thorned collar around his neck, Kyōka advises Atsushi to take it off, but Atsushi refuses. Explaining the pain is needed to control the tiger's strength, to keep the tiger from taking over. The Black Lizard comes across them, Atsushi thanks them for guarding the area. Hirotsu tells Atsushi to seek treatment at the base and report to the boss afterwards, going on to explain how they knew about the bombs and had Kyōka take care of them. Atsushi heads to the boss, Dazai.

Atsushi arrives at the headquarters and stands before a large double door, telling the boss that it's Atsushi, coming in regards to his summons. A voice replies enter and Atsushi pardons himself. Atsushi and Dazai talk about the assassins he had taken out, Atsushi was then told about his next mission. Dazai talks about how Akutagawa has joined a detective agency, now having entered phase 2 of the plan and it's time to start preparations for phase 3. Confused, Atsushi asks what Dazai is talking about. Dazai replies its the master plan, and that he is counting on Atsushi to slaughter the enemy without batting an eye, fearlessly.

Atsushi explains he cannot be fearless, saying he is a coward. Being shot at by guns, spilling his blood, Atsushi says it's very scary. Dazai recounts how Atsushi continues to massacre soldiers without showing emotions, to which Atsushi agrees, explaining that although he fears the battlefield, his body doesn't break a sweat ever since that time. Atsushi freezes in fear, a flashback of his orphanage director injured coming into view, when Dazai tells him that that time was when Atsushi ignored his orders and acted on his own. Atsushi becomes fearful and frozen, holding his head in his hands. Atsushi is asked of he still can't escape his fear of his death, Atsushi goes into a panic, telling Dazai he isn't afraid. Atsushi begs Dazai to give him his orders, saying he will never go against his orders ever again. It was then explained to Atsushi that his next target is the Armed Detective Agency.

Later on, Atsushi is seen entering a cafe. He sits beside another man, which is Akutagawa, and orders coffee. He then kindly asks Akutagawa if he said "detective agency" at the phone since he heard him talking. Akutagawa replies to him that he is a member of the detective agency. Atsushi then shares that his boss ordered him to deliver a letter to the president of the agency but he's lost and added the raining weather, he needed to take shelter. Akutagawa responds that the agency is at the fourth floor of the building to which Atsushi gave his thanks to him. The two then talked for a bit about their time in their orphanages.

Atsushi then decides that he can give the letter to Akutagawa and just pass it on to their president. Both of them asks each other's names. Atsushi responds to Akutagawa about who the sender of the letter is and that it is written on the letter and he will know it once he reads it. However, Akutagawa decides to check the letter to make sure it was safe. He then proceeds to open the letter and saw a picture of her sister. Atsushi asks him if he knows who she is to which Akutagawa angrily asks where she is and if Atsushi won't tell him, he will kill him. Atsushi then suddenly scrapes Akutagawa's neck and tells Akutagawa that their organization has a rule in which if a person asks about Gin's whereabouts, they should eliminate them. He also tells that since Gin is the secretary of their boss and stays with him 24/7, targeting her is equal to threatening their boss.The two starts to attach each other. Atsushi then retreats saying that it's not a good idea for him to fight directly under the enemy's base and he hasn't reported to his boss and leaves the cafe.