Dragon's Head Conflict

Dragon's Head Dispute (龍頭抗争, Ryū'zu Kōsō) is an underground conflict in Yokohama between various underground organizations. It lasted for 88 days and is labelled as the darkest conflict in Yokohama's history.

Background
The conflict started six years ago. An ability user died, leaving behind their humongous amount of fortune. Various of criminal organizations began to move, battling to claim it. The incident turned Yokohama into a bloody battlefield that lasted for 88 days.

Casualties involving the mafia, criminals and innocent civilians. In this conflict, Sakunosuke Oda rescued the five orphans who lost their parents to the crossfire. Sakura is the first orphan he finds and saves.

Tatsuhiko Shibusawa was involved due to the Japanese Government's intervention. They intended to have him settle the dispute, but instead he exacerbated it.

After discovering his comrades committed suicide, Chūya ultimately ended the conflict using Corruption. The Port Mafia emerged victorious thanks to Chūya Nakahara and Osamu Dazai, marking their new nickname as Double Black (双黒, Soukoku), the "most devastating rivalry".

Summary
Sakunosuke Oda enters a ransacked jewellery store, one used by GSS as more or less a shell company. His intention is to investigate who robbed the store, but he meets Tatsuhiko Shibusawa. Shibusawa mentions a corpse in the store, and the method of murder shocks Odasaku. He deduces they were killed by the culprit, but is still stunned at how one person could kill so many powerful ability users. Shibusawa argues it's not shocking, as it's a time of war in Yokohama, and ability users die all the same.

Odasaku asks Shibusawa if this is his first time in Yokohama, as so many deaths of powerful ability users, and attacking a group like GSS, is unheard of. Shibusawa dismisses it as a foolish criminal's attack. Odasaku asks about a rumour regarding a “White Dragon”, but Shibusawa says it's not his place to judge the culprit, and plans to take his leave. Just before he leaves, he reveals the culprit's “true intention”. A bored individual, the culprit idly takes anything that catches his eye. After this, he leaves Odasaku, saying he'd like to speak to him again if he's alive.

After he leaves, Osamu Dazai arrives, asking if Odasaku is okay. He explains he arrived after receiving some information, and asks Odasaku if a man with long white hair appeared. Odasaku confirms this, and Dazai says it's good Odasaku is alive after coming face to face with the White Dragon himself, a man trying to take over the conflicts.

70 days into the the conflict. Chūya wakes Dazai up from sleeping in his office, irritated by Dazai's nonchalance over the intense conflict. Summoned by the Port Mafia Boss himself, the two must attend a meeting alongside the other higher ups.

Dazai, knowing the happenings outside, continues to tell Chūya the details of the war; the casualties caused by the overseas organization - 'Strain', the death of 'Takasekai's leader which lead to its collapse, as well as the casualties suffered by the other organizations. Dazai tells Chūya to leave the dispute to Mori, as there lies a more concerning activity.

He shows Chūya a photograph of a corpse, later revealed as one of the Mafia's Executives, codenamed 'Colonel'. His death creates an empty seat in the Five Executives. Chūya doubts the 'Colonel' could die so easily, mentioning that the deceased man is one of the strongest Ability-user in Mafia's ranks. Dazai tells him the killer is the 'White Dragon', however, not even Dazai knows the White Dragon's ability.

While Chūya says he will kill the culprit himself, Dazai insists both of them should be more concerned about the Executive Candidacy. Chūya dismisses the statement, leaving Dazai alone.

Later, Shibusawa reappears, noting the streets are more populated than normal considering the ongoing war. He approaches a florist, asking her for a bouquet of white flowers, but the woman reveals a gun. The woman, alongside all the other 'citizens', are part of a faction Dazai leads. Dazai confronts Shibusawa himself, bluntly telling him he won't hesitate in killing him, and that, no matter how powerful the ability, a "one man army" stands no chance against a juggernaut faction of ability users like the Port Mafia.

This concept interests Shibusawa, who asks Dazai if "power in numbers" is why Dazai joined the Port Mafia, to which Dazai confirms. Their conversation continues, and in the end Dazai states that while he can let go of the death of 'Colonel', he is not kind enough to leave Shibusawa alive.

Involved Parties

 * Port Mafia
 * Tatsuhiko Shibusawa
 * Fyodor Dostoyevsky
 * GSS
 * Special Ability Department
 * Shadow Blade (an arms dealer)
 * Bishop's Staff (a religious organization)
 * KK Company (contraband merchants)
 * Takasekai
 * Strain (overseas organization)

Post-Conflict

 * The five orphans are adopted by Sakunosuke Oda.
 * Takasekai's leader is killed, leading to the organization's demise.
 * 'Double Black' forms.

Trivia

 * Sometimes, it is known as Dragon's Head Rush in the international fandom.
 * The conflict is used as one of the major causes of "Dead Apple".
 * The conflict's details are elaborated upon in an event from Bungo Stray Dogs: Mayoi Inu Kaikitan.