Osamu Dazai (BSD) - Oda/Book/Universe Theory
So... I've been thinking really hard about bsd, specifically Dazai and his connections to Odasaku and the Book (ie. the beast au too).
Warning: It might not be 100% correct as I've never read beast or the light novels and am currently rewatching bsd now.
So, anyways... I've been thinking, we all know B!Dazai was following the same route as OG!Dazai up until around the time he met Oda for the first time. Afterwords, Dazai came into contact with the Book and had his whole singularity moment where he saw what we call the OG universe, leading to the changes that happen within Beast and the outcomes of those decisions. What this means is our Dazai would have had to have the same phenomenon happen, meaning the theory that Oda was in possession of the Book at some point might be true.
But how does that connect with OG!Dazai?
Well, what if we aren't viewing the actual OG!universe of BSD... what if the proper OG was another past universe and our OG is simply another variation of the proper original?
We see that Dazai (one of them) created infinite universes where he tries to save Odasaku, but fails. Meaning Oda is essentially the core of each universes survival; sure the lives of others may go on after Oda's death, but Dazai doesn't. Leading to the more universes being created. What I mean is Oda is the sun and Dazai is his planet that forever orbits around him, and without the sun, the planet is dead.
I say this because while we don't know what happens in the other universes outside of Beast, the entire point has been clear that the motive behind the universes creation was for Dazai to save Oda; only he failed each time. So, what if within the Book, those universes are scrapped and left to write themselves by the ones remaining, but that universe no longer holds any value to Dazai and so the Dazai's in those universes 'die' in some way, shape or form. After all, Oda didn't survive and Dazai felt no need to continue.
This leads me to my theory that our OG world isn't the original, because as I stated, Dazai has often hinted at the idea that he knows what the Book is and how to use it throughout the series. So what if similarly to B!Dazai, before Dazai met Oda in this universe, he came into contact with the Book and saw these alternate universes, ie. before B!Dazai, but unlike in some of the other universes, Dazai chose to bring Odasaku into the mafia and stay by his side in hopes that nothing will happen on account to him being a powerful executive (after all, Dazai became an executive at 16, around the time he met Oda), so Dazai gaining the power might have been tied to Oda from the beginning; similarly why he was so dead set on recruiting Chuuya.
Because he already knew who he could trust as well as those he could use in the long run.
I reference this to the quote "Everything I never want to lose is always lost... that's how it's always been for me." and the quote from Kouyou; "Dazai has already seen how all of this would play out" meaning if he had knowledge of what came up until Oda's death, it would explain why the mafia thrived under his leadership and command. Why Mori is dead set on bringing Dazai back despite his fear because with Dazai he can predict what is to come with the oncoming conflicts.
What if our OG!universe was the one the creator chose to focus on because it's the only universe in which Dazai persues life AFTER Oda's death. After witnessing so many universes in which he fails to save Oda, and having Odasaku say his last words; for Dazai to live on and "protect" others... This universe would allow Dazai to continue his path by giving him another reason to live (outside of his failing to save Oda), by having him live to achieve Odasaku's last wishes. It would still allow for Dazai and Oda's planetary orbit to continue, even if one of them is no longer alive.
It could also be why Dazai is unable to commit suicide properly, and how no matter how injured he gets, he will always come out on top, as he is seen as one of the two individuals that allow for the universe to continue it's cycle. But it could also tie into why Dazai's ability is called "No Longer Human", even if the abilities are simply named after our RL!authors.
I say this because the understanding of BSD!abilities is that they are tied to one's soul, and by either association of the poetry or by actively hearing those words does the ability activate for the first time, it's why people can live their lives never knowing if they had an ability or not.
And while the idea that Dazai came from an abusive household prior to the mafia might be true, Dazai's suicide attempt might have actually been in connection to the alternative universes and the Book, much like B!Dazai, attempting to unalive himself before he had the chance to meet Oda and cause the death of his long time friend in the future. Meaning, the Book and the universe itself would have intervened, "guiding" Mori to Dazai, who saved him and took him into the mafia where everything continued sailing; and no matter how much he tried to end his life, each attempt failed because the universe is getting desperate to keep the world going after so many failed attempt.
After all, we don't know the author behind the Book, and the idea that it can change reality... the idea that the Book came about from the universe itself and not a regular ability user might make more sense.
This might also tie into the idea of Fyodor too because as far as I'm aware (not read beast, but have heard a lot about it), Fyodor never appeared in the Beast universe.
This could mean that because Dazai is continuing to live by Odasaku's last wishes, the world is having to introduce new threats and challenges to keep Dazai in the game because after a while, Dazai might get bored and decide he's done. That there's no use in continue his existence because he's saved what he deems "enough" people. And by adding Fyodor, someone who is on the same level as him intellectually, Dazai can feel alive as long as he is mentally stimulated and challenged; his mind is less on suicide and more on defeating the big enemy that poses a threat to the peace and safety Oda wanted Dazai to witness.
Because if there's one thing I've noticed in the beginning of bsd to the point I'm at in the series and the spoilers I know from the later season, is that Dazai attempted to commit suicide quite a lot during the earlier season, but doesn't make as many attempts when his mind is occupied on a tough case that distracts his boredom.
// Now I might be wrong as this is simply a theory, given Dazai is a complex and mysterious character we honestly don't know much on outside of Oda and his time in the mafia and ada. I mean, there's also the time he was in hiding between that we have no idea where he was or what he was doing. But I hope people like my theory anyways, even in the event that it might be complete nonesense haha. //