Osamu Dazai

"Motto: Have a pure, cheerful, and energetic suicide."

Osamu Dazai (太宰治,) is a member of the Armed Detective Company and was a former member of the city's worst underworld organization, the Port Mafia.

Appearance
Dazai has mildly wavy, short dark brown hair and narrow dark brown eyes. His bangs frame his face, while some are gathered at the center of his forehead. He is quite tall and slim in physique.

For his attire, Dazai wears a long tan trench coat over a black vest and a striped dress shirt that is light blue in hue. He has a bolo tie around his collar, which is held by a brown ribbon and a turquoise pendant. He also dons beige pants, dark brown shoes, and has bandages wrapped around his neck and forearms, the reasons for the bandages are yet to be discovered.

Back when he was in the mafia, Dazai wore a dark trench coat that reached under his knees. He also wore bandages over his right eye and his right arm is in a sling—presumably products of his suicidal pastimes.

Personality
Dazai is a mysterious person, his true intentions are never revealed unless he himself reveals them. The person who got closest to the truth of his personality, as acknowledged by Dazai himself, was his friend Sakunosuke Oda, who said to him, "It can't be found. (...) You should know this yourself. No matter whether you're on the side of killing people or saving people, there will never be anything that can surpass your mind. There is no place in this world that can fill your loneliness. You will linger in the darkness forever."

Dazai is usually called lazy as Kunikida always scolds him for being unproductive and slacking off. Despite that, he has shown a sharp wit, deducing all the unlikely situations that led Atsushi to believe he was being stalked by a tiger when he actually was the tiger in question. He has complete confidence no matter what type of situation he is dealing with, be it combat or simply bad situations he himself created in the first place. In most occasions, Dazai is overly dramatic, he takes most of his actions as a joke, and although they are very thought out plans, he does not credit himself for most of what he has done.

Aside from his quick thinking, Dazai is the comic relief in the series and at times Dazai's soft side can be seen.

Ability
His ability, No Longer Human (人間失格,), lets him nullify others' abilities on contact. His ability relies on skin contact, so he is unable to use it when he is restrained which is the only disadvantage to his ability.

Dazai Osamu and the Dark Era
Dazai was a part of the Port Mafia prior to the story, and he was once one of the five great Port Mafia Executives. He was the youngest person to become an executive in history (being considered as an executive before he was even 16 ), and a living legend within the mafia as well—to the extent that there is a saying going around the mafia: "The misfortune of Dazai's enemies is to have Dazai as their enemy". In the years he was an executive, roughly half of the mafia's overall profits could be solely attributed to him, to the extent that Ougai Mori mentioned that, "Given another four or five years, I wouldn't be surprised if Dazai killed me and took over my position." He was also a specialist at torturing people for information claiming to Kouyou Ozaki that, "There hasn't been a single prisoner, who hasn't spilled everything under my interrogation." . He even gave Akutagawa spartan training in using his ability, and even gave Akutagawa the idea of cutting space itself to shield himself.

The trigger for Dazai leaving the mafia was his old friend Oda Sakunosuke, a low-ranked mafia member—who was killed in the conflict between Port Mafia and Mimic, orchestrated by Ougai Mori to obtain an official license from the government expressing silent consent of Port Mafia's existence and its activities as an organization. Already distraught from the knowledge that Ougai intentionally drove Oda Sakunosuke into a suicidal attack against the enemy commander, Dazai took Oda's last words to heart—"I know it makes no difference to you, but please become a good human being. Save the weak, protect the orphaned. I suppose you don't care for either justice or evil...but striving to be a better person is a wonderful thing"—and decided to leave the mafia. He was 18 years old.

It is stated by Akutagawa that, during a mission, he suddenly aborted it and supposedly, defected from The Mafia. Dazai later tracked down a man named Taneda, who was the acting commander for the Japanese ministry's Special Abilities Division, and requested to work in a place where he can help people. Taneda recommended the Armed Detective Company to Dazai, on the condition that he'll need at least two years laying low to cleanse his past. Later, it was his friend, Ango Sakaguchi who assisted him with that. It is unknown what he was doing during those two years, but it is mentioned by Dazai himself that before meeting the Armed Detective Company, he was an unemployed and unmotivated and drunk in a bar that he used to frequent.

Dazai Osamu's Entrance Exam
At the age of 20, he joined the Armed Detective Company, and—as a newbie—was entrusted by the Director to Doppo Kunikida. Shortly after, were both assigned to work on the Serial Disappearance of Yokohama's Visitors Case.

Plot
Dazai first appeared floating down a river, apparently trying to commit suicide until he was accidentally found by a starved Atsushi. Afterwards, he and his colleague, Kunikida treated Atsushi to food while listening to his story about how he ended up at the river while hungry. He then introduced himself and Kunikida as part of the Armed Detective Company and they would like to hunt down the tiger that is apparently following Atsushi and terrorizing the areas wherever he went.

At night, while Dazai and Atsushi waited for the tiger to show up, he realized all of the clues that led Atsushi to be confused about the tiger was matching up to be the fact that Atsushi actually was the tiger. As Atsushi lost control of himself and transformed into a full-grown tiger, he was easily subdued by Dazai's ability, No Longer Human and lost consciousness. Dazai then brought Atsushi back to the dorm where the Agency members are staying. The next day, he called Atsushi for help because he was stuck in an oil barrel trying to commit suicide and gives him the address of the Agency at the same time.

Quotes

 * (to Oda Sakunosuke) "Success is harder than failure for many things in this world, right? (...) That means I shouldn't place suicide as my goal, but rather, attempted suicide! It may be harder to succed at suicide, but to fail at attempted suicide should be easier!"
 * (when asked how he got a few of his injuries by Oda) "I was reading a book titled 'How to Prevent Accidental Injuries' while walking when I accidentally fell into a ditch. (...) I was speeding on a mountaintop when I fell into a precipice. (...) I was trying out this suicide method of hitting one's head on the corner of tofu."
 * "Disputes that become worse because of me... how wonderful."
 * "You're an idiot, Odasaku, you're a big idiot! (...) To accompany this sort of guy into death, you're an idiot!"
 * (after eating a hallucination-causing mushroom) "Hohohohoho, as expected, The Complete Suicide Manual is a masterpiece! Just by eating the mushrooms growing on the mountain trail behind, I am able to go down such a happy and pleasant road towards suicide! (...) Hey, hey, Kunikida-kun, come on over to the Underworld too! Look, the alcohol are free-flow, there's endless food, and you can smeel the pretty ladies all you want! (...) Wow! Kunikida-kun, there's a gigantic sea anemone outside the window! Banana! It's eating a banana! It's taking away all the white party blowers around us! (...) I get it! I'll strip; if I strip, the viewers' ratings will go up! It's not an easy task but let's strip, then as a change, let's put on full-body tights! Everyone wearing tights, going to the bank, then dancing the Cossack Dance! (...) There's a voice... urgh, he's—he's inside my head!... A small gramps! And he's whispering to me to go to Kyoto, there's an authentic tofu with a unique flavor that I have to tr—"

Trivia

 * He, along with several other characters, made an appearance in the mobile game Love Heaven as a limited time character.
 * His constant attempts to commit suicide with a beautiful woman could be an allusion to his real life counterpart's attempted double suicide with Shimeko Tanabe and Hatsuyo Oyama. His attempt with his lover Tomie Yamazaki was ultimately successful.
 * It's also possible that his suicide attempts serve as a reference to No Longer Human 's protagonist Ōba Yōzō's multiple suicide attempts throughout the story, which is considered to be a reflection of Osamu Dazai's turbulent life.
 * He was the youngest boss in mafia history.
 * In real life, he is often grouped together along with Sakaguchi Ango and Oda Sakunosuke as the Buraiha or Decadent School. 
 * And on the series, this is often alluded, because the three used to meet in a certain bar, as seen in Dazai and the Dark Era, and illustrated on the calendar.
 * He is nicknamed as 'Bandage-wasting Device' by Kunikida at Chapter 2 / Episode 2.
 * Dazai usually refer himself by gender neutral phrase "watashi" rather than the more masculine phrases like "boku" or "ore".
 * Dazai's pretty bad at driving, as shown in the first light novel "Dazai Osamu's Entrance Exam".
 * He is based after Osamu Dazai, a man who wrote No Longer Human.