No Longer Human

Verified Timeline

Lore & Background

The text explicitly details that 'No Longer Human' functions by nullifying other abilities through **physical contact**. This mechanic is central to Dazai's strategy in resolving conflicts involving the Port Mafia and Fyodor Dostoevsky's groups, including the eventual arrest of Dostoevsky alongside Atsushi and Akutagawa. Despite his past imprisonment, Dazai remains a central operative, forming alliances with former enemies like Francis Scott Key Fitzgerald to counter the Hunting Dogs and the Decay of the Angel.

In Their Own Story

After being kicked out of his orphanage, Atsushi Nakajima saved Osamu Dazai from what appeared to be drowning in a river, only to learn it was a suicide attempt. From this encounter, Atsushi discovered that Dazai possessed a supernatural ability, which Dazai used to recruit him into the Armed Detective Agency. Later, during a major conflict involving the Decay of the Angel and the Hunting Dogs, Dazai managed to arrest Fyodor Dostoevsky after cornering him alongside Ryūnosuke Akutagawa and Atsushi. In the prison where they were held, it was revealed that Dostoevsky's ability allowed him to take the body of whoever killed him; however, the text does not explicitly describe how Dazai's specific power functioned during these arrests beyond his general role in neutralizing threats.

Reader's Guide

The provided source text does not contain a functional guide for 'No Longer Human.' It confirms that Osamu Dazai is an ability user who recruits Atsushi and helps arrest Fyodor Dostoevsky, but it omits specific instructions on activation methods, range limitations, or the exact nature of the power's effect (e.g., nullification). The text mentions that Dazai's design contrasts with Ryunosuke Akutagawa and that he acts as a 'sage' figure to Atsushi's hero role. While it states that characters are named after authors whose powers are based on their books, the specific rules governing Dazai's ability are not detailed in this source.

Did You Know?

• Writer Kafka Asagiri was inspired to create the character Osamu Dazai after reading No Longer Human and finding relatable the author's expression of embarrassment involving his entire life.
• Osamu Dazai serves as a 'sage' figure in the story, acting similarly to Merlin to King Arthur for the protagonist Atsushi Nakajima.
• While Kafka Asagiri is known for various online works, the specific claim that his video 'Yukkuri Youmu and the Really Scary Cthulhu Mythos' reached 1 million views prior to his editorship is unverified; trivia typically
• Asagiri described his writing process for character backgrounds as 'mysterious,' noting it typically took him between two or four days to complete.
• Sango Harukawa, the illustrator, always wanted to draw a white tiger, which influenced the design of Atsushi Nakajima's ability.

Origins and Creative Inspiration

The character of Osamu Dazai was created by writer Kafka Asagiri, who found inspiration in reading the author's book No Longer Human. Asagiri expressed that he felt a connection to Dazai's expression of embarrassment involving his entire life, which motivated him to create a version of the character that would stand out among readers. Following the selection of Atsushi Nakajima as the main character, Asagiri needed a third character to act as an equal to Dazai, leading to the creation of Kunikida. The writer described the process of developing these characters and their backgrounds as 'mysterious,' noting that he could complete background drafts in two to four days. Sango Harukawa provided designs that helped Asagiri create stories more easily, with specific revisions made to ensure Dazai's design heavily contrasted with Akutagawa.

Narrative Arc and Supernatural Conflict

The story follows Atsushi Nakajima, a weretiger who joins the Armed Detective Agency under Osamu Dazai. The narrative expands as they face Ryūnosuke Akutagawa of the Port Mafia and Francis Scott Key Fitzgerald of the Guild. A major conflict arises when Fyodor Dostoevsky uses a virus ability user to clash the detectives and mafia, leading to Dazai arresting him. Later, pages of 'The Book' are found by Dostoevsky's group, the Decay of the Angel, framing the Agency. As the situation escalates with the government's Hunting Dogs, Dazai is imprisoned but later forms an alliance with Fitzgerald and the mafia. The climax involves a confrontation where Atsushi defeats a god-like entity created from Fyodor's abilities, after which the Detective Agency is forced to close.

Adaptations and Media Expansion

The manga began serialization in Kadokawa Shoten's Young Ace on December 4, 2012. An anime television series adaptation produced by Bones aired in two parts in 2016, with a third season in 2019, a fourth in early 2023, and a fifth from July to September 2023. A film titled Bungo Stray Dogs: Dead Apple was released in March 2018. Ten light novels had been published as of 2025. A spin-off series, Bungo Stray Dogs Wan!, aired from January to March 2021, with a second season scheduled for July 2026. Additionally, a live-action film, Bungo Stray Dogs The Movie: Beast, was released in Japan in January 2022.

Character Dynamics and Thematic Depth

Osamu Dazai serves as the 'sage' to Atsushi Nakajima's hero role, contrasting sharply with Ryūnosuke Akutagawa. The author Kafka Asagiri designed Dazai based on the emotional core found in No Longer Human, aiming for a character that readers could connect with due to his complex nature. The narrative explores themes of redemption through characters like Kyōka Izumi, who transitions from an assassin for the Port Mafia to Atsushi's partner. Villains such as Francis Scott Key Fitzgerald are written to be relatable despite their destructive actions, driven by personal desires like protecting family. The story questions the lines between justice and terrorism, particularly with the arrival of the Decay of Angels and Hunting Dogs.