The Japanese shorthand for the series is '文スト', which translates to 'Bunsuto', which in itself is short for 'Bun-storei' (Bun-stray). Due to the way there always needs to be a vowel after a consonant, 'storei' almost sounds like...'story'.
Why is the Armed Detective Agency called like that, while they don't really do detective work? Because it was created for the only detective in the team.
The title of the first ending theme, Trash Candy, pertains to the very reason why the series exists. Most writers aren't revered until their works are almost forgotten (trash) but we found it to be something to be enjoyed (candy).
Why are there no official character sheets of Tachihara and Gin in the manga? Tachihara is a traitor who possesses an Ability, and Gin's full name is Akutagawa Gin.
Why is Atsushi so much worth on the Black Market? It's something of all factors combined.
There's the thing that Atsushi is the key to The Book.
In real life, tigers are endangered especially because of their fur and other parts of their body can be sold for millions of dollars.
Their body parts are used for 'medicine' (loosest definition), and Atsushi's tiger can regenerate. Imagine how much worth they'd be.
Speaking about Atsushi, he seems to fall back into Wangst everytime a new arc starts. But this is very common for actual PTSD victims, who never actually get over their traumas and need lifelong assitance to help them cope a little.
Why is Atsushi specifically a white tiger? Because they're mainly white with a bit of black (stripes) like Yang.
Related to that, people complain about how character development is erased between episodes (such as the aforementioned Atsushi Wangst). However, this happens all the time in real life. It's incredibly rare for people to permanently get over their flaws, especially when factors like how people recently treated you or even what dream you had that morning can have huge effects on your mood, confidence, and actions (related and unrelated).
It may seem like Fyodor is nothing more than a psychopathic mastermind (and it may seem even more like that in the anime than in the manga, due to several scenes being Adapted Out), but this isn't the case. First he kills Ace, gaining control over several important files concerning the Abilities of the executives and the boss (meaning that Fyodor knew exactly what Mori's Ability entailed, making it possible to make a skeleton of a plan based on that knowledge alone). Then he uses a (brainwashed) Hawthorne, because he knows that Akutagawa would go after him because he knows The Scarlet Letter the best. He makes Hawthorne blow up the car Mori's in, but not to kill him - just to create a massive crowd of bystanders to flee in when he applies the curse himself. Fyodor isn't insane; although he has some delusions, he's very much calculated and in control of his actions!
When Atsushi pushes a baby in Tachihara's hands during his mission to bring the doll to Dazai, Tachihara is notably shocked and confused. Probably not only because of the suddenness, but also because he now feels like an older brother.
Akutagawa and Atsushi are designed to go together, and even if it might not be officially so, it certainly looks that way...when you look at the series this way, the symbolism is as subtle as a brick:
Atsushi's design is mainly white with a tinge of black, while Akutagawa's design is mainly black with a tinge of white. This is most prominent in the hair.
The colors of these powers are white and blue, and black and red, respectively. To reflect this, on episodes where they work together (Such as the season endings), they often show both colors. At the end of season 2, the title cards was blue and white instead of black, red and white, and at the end of season 3, the first logo shown was red with black letters, while the last logo shown was white with blue letters.
On a deeper level: 'Ryuunosuke' means 'son of the dragon', because the real-life Akutagawa was born in the Year of the Dragon, in the Month of the Dragon, at the Hour of the Dragon. The tiger and the dragon are often at odds with each other in mythology and maintain the peace. The contrast fits as well, with Atsushi recklessly charging at things, and Akutagawa using his power in various different ways.
The real-life authors they are named after, had a very different style of writing as well.
Mii-chan/Sensei is consistently referred to with male pronouns, although it's a calico kitty. Meaning the chances of it being actually male are small...which is a very early hint to that it's Natsume.
Dazai is frequently likened to a fox, and certain merchandise features him as a Kitsune. Not only are these creatures known for being cunning...but they also can be thwarted by the presence of dogs!
Interestingly enough, in that same merch art, Odasaku is depicted as an inugami...and Odasaku and Dazai can never be friends, in any timeline, without Odasaku dying.
Why is Poe's Ability called after not one, but two books and makes it seem like one? note More specifically, 'The Murders in the Rue Morgue' and 'The Black Cat' Well, remember what it does? Place others into a story, or rather, transport characters in a story to another one.
Also, why does he dress like a gothic gentleman who's Born in the Wrong Century and is somewhat of a loner? Because his namesake was a writer who inspired the goth subculture, among others.
Meta: The fact that writers and poets are the one who get powers, and the characters in their stories don't (i.e, Junichirou does and Naomi not). Writers are a special kind of people if you think about it - they can create entire worlds in their books and make people feel things, controlled by their own words. The jump from this to 'magical powers' isn't that big to take. This is also why every ability is called after a book or a line in a poem of some sorts, and the effect beams are composed of words if you look closely. It is a big part in the reveal that Tachihara has an Ability.
The magical item several characters are after is a Reality-Writing Book. They're writers. Duh.
About the Guild... If you aren't interested in following the link, the short of it is that they are based on The Freemasons.
Also, most, if not almost all of their namesakes were writing during the gilded age.
Why wasn't Hawthorne present during the Cannibalism arc? The virus infects people through open wounds and that is basically Hawthorne’s ability! He has to create an open wound and use his blood to attack, so he’d be infected immediately.
Why does Atsushi still have scars from the orphanage, although being able to regenerate? That is because he used to only be able to regenerate in tiger form. It is when he joins the Agency, that Fukuzawa makes it so that he can regenerate when not in tiger form. The people in the orphanage likely did not have the tools or courage to wound him in tiger form, and everytime the headmaster is shown wounding him, is when he is in normal form.
In chapter 48, how were the Lizards aware of Tanizaki's Ability? Because all the way back in chapter 3, Tanizaki fought against Higuchi, who is the superior over the Lizards! She must've told them somewhere in between.
The Sheep (Chuuya's affinity from before he joined the Mafia) show no sign of respecting Chuuya, who should be a leader, having an Ability and all. There is also no sign of the Sheep having an actual leader. Real sheep have no hierachy, hence why these things happen - all sheep just follow the sheep in front of them. Even the Bible uses sheep as a metaphor for people in an anarchy.
The anime has added a new symbolism scene in Season 3. The last cards A shows to Fyodor during the game of high/low, are the Four of Diamonds and the Ace of Spaces. Ace is also how 'A' is pronounced, and Four is, well...
Why is Louisa so dependant on Fitzgerald? Her power slows down time, but only if alone. In the world of Bungou Stray Dogs, that is ridden with fight between Ability Users, she would definately lose (as her age is stated to be just 18). Fitzgerald is likely the first one to put her Ability to functional use.
Of course Gogol survives his apparent death - being sawed in half is the oldest circus trick!
Chuuya and his supposed older brother are both named after poets, Chuuya Nakahara and Paul Verlaine, respectively. Also, Chuuya is linked to both him and Rimbaud - to the point that the real Chuuya is nicknamed 'the Japanese Rimbaud'.
It is only natural that Ryuunosuke (lit. 'Dragon son') was the first to be infected by Bram Stoker, who wrote Dracula (lit. 'Dragon son').
Quite a few things have strangely been given explanations after Storm Bringer.
Some of the experiments performed on Chuuya gave him enhanced strength and durability, so his ability to kick a person into a wall hard enough to leave a crater without using his powers makes a lot more sense.
The experiments also made him weak to poisonous substance- alcohol can be considered a poison, and Chuuya has a pitifully low tolerance to it.
His exceptionally small size could also be attributed to the fact that he was horribly malnourished and emaciated after escaping from the lab, which likely stunted his growth.
During fights, Chuuya commonly takes off his coat and will remove his gloves to use Corruption, but he never removes his hat despite how easily it could fall off, in fact, he often makes an active effort to hold it down on his head. It turns out he needs his hat to activate Corruption and anyone else who knows the Trigger Phrase could do it if they somehow got ahold of it.
During the Fifteen arc and Storm Bringer, Chuuya had a fairly mundane fashion sense and dressed rather plainly, especially compared to his current attire which is formal and stands out. During the aforementioned light novels, Chuuya was struggling with an identity crisis and didn’t known who he was, with his apartment being described as empty and him not thinking about what he wore. He began dressing more boldly and personally after his issues were resolved and he forged his own identity.
Chuuya likely became an executive when he was at least eighteen. It's known that he was promoted at some point after Higuchi joined as he takes her and Akutagawa with him to observe his supposed birth parents when Mori gives their location to him as a gift for becoming an executive. However, given that Higuchi did not know Dazai before meeting him during the main series, it's safe to say she joined after Dazai left, thus putting the time when Chuuya was promoted to any point within the four years between Dazai leaving the mafia and resurfacing.
More like Fridge Tearjerker, but remember those drinks Dazai, Oda, and Ango had during the Dark Era arc of the anime? Well...
Crossing over between Fridge Tearjerker and just plain Brilliance, there is Dazai's bandages. He seems to have them for no reason at all and can be explained easily as just a design choice. But this is Dazai we are talking about, and he used to be even more covered in bandages during his time in the Port Mafia, when his desire to die was more serious and not the slightly more lighthearted Running Gag it would become later on. You dothe math...
In Yosano's backstory, we see that Elise is quite different from now. She wore different clothes, and seems more to be like a house robot than a normal girl. She also seems to be older, and last but not least, she calls Mori 'Master' instead of 'Rintarou'. However, in chapter 50, we see Elise being more similar to what she is now and if you look at the timeline, you notice that that chapter actually takes place after Yosano's backstory. Yosano back then was a young girl under the age of 12 (she was 11), had a fierce temperament and wore nurse's clothing. What does Mori's Ability do again? Oh, yeah, it creates a thing he desires... (better worded here)
More Fridge Depressing: It has been established by Word of God that in every single timeline, Odasaku is doomed to die. No matter what. That's right—Odasaku is unable to be saved. He is completely and utterly doomed.
This also implies that even in the Gakuen universe, he will die...let that sink in.
If Fyodor gets his wish and takes away everyone's Abilities, that spells bad news for Chuuya no matter how things work out. If he somehow kills all the Ability users, Chuuya obviously dies, but if Fyodor manages to only eliminate their Abilities, Chuuya would only have minutes left to live as he cannot survive without For the Tainted Sorrow.
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