Writing a complex character such as Dazai is actually really hard even for people who understand him because he is, as you said, extremely unpredictable. I don't know exactly what to tell you, but I'll try to help a little bit!
The whole thing about Dazai is that he doesn't understand humanity. He understands the basics and why people do what they do because he is analytical and has been studying people's behavior and human connections forever. But he doesn't feel connected with humanity and empathy the same way other people do. He perceives others from like, the other side of a barrier. He studies them carefully. Manages to care about them deeply sometimes. Even deeper when they're able to see him and get to him (Odasaku, Atsushi, Chuuya, the whole agency in fact means something to him). But there's always this layer of disconnection and apathy and emptiness he doesn't know how to get rid of. It's like he cares, but he actually doesn't because he rationalizes everything and turns it into a game of chess, more or less? And I think that frustrates him. He isn't used to caring about people because he doesn't understand them, but he takes an interest in the people he finds amusing to study and once he cares deeply, they're taken away from him (that's why he mourns and regrets Oda's death so much. He feels like the world takes everything away from him the second he manages to feel human). Hence the whole thing about not feeling human (amongst other things). He cares and yet he is realistic. He has regrets and suffers and feels pain and he can care about others (ignore all the people who keep portraying him as an emotionless monster, please) but he doesn't drown in self-pity when it comes to all the people he has killed and his past because he can rationalize that. It was another era. He has moved on. And if it's for the greater good of the mission or his journey to find something to live for, he doesn't care how many random people he has to kill (when he was younger he valued other people's lives way less, of course. Now that has changed because his apathy is something he doesn't turn into cruelty and instead uses to rationalize plans and help the world and the agency. Basically, when he was part of the mafia it was kind of "I don't give a fuck about random people" because he genuinely didn't feel anything for them, but now, even if he doesn't genuinely care for them, he protects even random people because that's what the image of kindness Oda had planned for him). Oda tells him that, if the good side and the bad one are the same and he hasn't found anything to live for yet, why not help the world while he's at it? And it's such a beautiful thought because Dazai has this issue with understanding humanity and making bonds. But he understands, now more than ever after Oda's death, what living and killing means. He might not actually care that much for society and its well-being, but maybe he can find something to live for in the light more than he would in the darkness. He keeps wanting to kill himself, right? He keeps trying. But he doesn't actually want to. It's common sense. If he truly wanted to, he already would've done it. "I don't like pain" is the most common thing to say when you don't actually want to do it. I think that, unlike Nikolai, who actually craves to die as a representation of freedom, Dazai only wants to keep trying and trying to find a reason for living. Chuuya was that thing when he was in the Mafia. Chuuya and Oda, because Chuuya is quite literally his soulmate (in the sense of bringing amusement to his life and also making him feel human, as his ability is the only thing that can help Chuuya. And also Chuuya not being human but being the most empathetic and emotional of all the people Dazai has met in the mafia) and Oda was the first one to actually understand him and see him for who he is, something I don't think he'll ever find again and that's why Oda's death fucked him up so bad. He found a place to belong and somebody to live for, and then he dies and leaves him alone? It's not fair, but he'll try to fight for good and live in the light if that's what Oda wanted for him. As if Oda knew him better than he knows himself because I also think he has a hard time with his own perception and personality.
In simpler words: Dazai has a hard time understanding humanity because he feels disconnected from it by a layer of apathy and the fact that he doesn't understand basic human needs/actions because he doesn't share them. One of the things that makes us human is desires, right? Wanting. Loving. Longing. Dazai rejects all of that because he doesn't know what he wants and nothing he tries ends up making him feel whole. In "No Longer Human", actually, you can read things like "It is almost impossible for me to converse with other people" and "I have never known what it means to be hungry / Eat or die, the saying goes, but to my ears, it sounded like just one more unpleasant threat". So he isn't a monster, his brain just functions in a different way. He sees everything. Analyzes every little thing. He's smarter than everybody else and he's aware of that, but he feels lonely there and only wants somebody to understand or something to fight for. Oda gave him both things, and the agency gave him a reason to keep going because he genuinely cares about doing good and keeping them safe. I don't think Dazai's journey has ended, because he still fights against.... So many things with himself. His past. His future. His desires. But at least now he has a thing to enjoy and bring him happiness. His constant act of being "silly" isn't that much of a facade. I mean, I think it is because if he acts like a clown, nobody will ever see the true self he hides. But I think he ends up having fun with the agency and annoying Chuuya because he sees them respond to his behavior and he finds it amusing. I think being extremely smart and lonely and tormented can coexist with being fun sometimes.
As per writing in his POV.... It depends on what you want to write, really. I think his brain functions differently depending on his mood. I guess the most important thing is to keep in mind his surroundings because he's always hyperaware of every little thing. But it frustrates him not knowing how he's feeling or not understanding what he actually truly needs, often focusing on others instead of looking into himself, because every time he does, he only finds himself empty and craving for something he doesn't know what it is. In his worst moments, I think it's quite obvious he tries to fix things with distractions and impulsive actions like substance abuse. In his more analytical moments, it's when he becomes more apathetic and sees the world as his game of chess and people as only pawns. He knows he's human, he just doesn't feel like it. Fyodor has a sense of superiority Dazai doesn't share. He's smarter because his brain functions differently, but he is no God. He is no entity. He analyzes from the POV of somebody external to humanity but knowing quite well he isn't God. And when he's having genuine fun and feeling some type of care/love? I think he's grateful. The emptiness is always there, though. Always haunting him. In the back of his brain. But he sees hope in Atsushi and a place to keep his promise in the agency and maybe fulfill his heart. He might always have a fucked up perception of himself, but at least he's aware that doing the right thing fills the hole in his chest more than tormenting others. As I said, he likes it there (and Chuuya) because it makes him experience humanity even if he keeps telling himself he isn't human (No Longer Human quote: "You miss her, don't you?" / "Yes." / "That's human nature, I guess").
I don't know if I helped you?? I think it's a bit of a mess, sorry 😠It's like 3am and I don't know if what I said makes any sense, but I really hope I was able to help you!
holy FUCK it took me fifteen minutes to read all of this and i'm glad i did because this is the most succinct and articulate analysis i have ever seen of dazai's underlying nature and his ambitions in relevance to the plot OP I THINK IF ASIGIRI CANT WRITE ANYMORE YOU SHOULD TAKE OVER BSD MANGA BC I THINK U UNDERSTAND DAZAI BETTER THAN HE DOES SOMETIMES TBH💀💀 aaaa jkjk i digress you were so real for bringing up the yozo/dazai parallels bc there's genuinely so many and if i still had my fucking BOOK :side eye: i could go through the intricate and profound commentary i left in the margins but alas my dear friend insists on keeping it longer. there's nothing more i can say on this topic bc i agree w you on everything wholeheartedly i think you deserve a scholarship to harvard or smth bc god DAMN you would slay as a lit or lang major
beeeeeeeen spending most their lives living in a gangsta's paradise keeeeeeeeep spending most our lives living in a gangsta's paradise
Relatable if you ask me
love languages according to soukoku
physical touch (violence)
words of affirmation (insults)
quality time (fighting other people)
gift giving (bombs)
acts of service (whatever the fuck that one scene in dead apple was)
blue sky sunny day
Devotion is nothing like mindlessly killing oneself with hopeless sentimentality. There is an immense difference. Devotion is to live a worthwhile life forever. Humanity is immortal only by relying on this pure devotion. However, there is no need to dress up for devotion. Today, I should offer everything as I am. The plowman should show devotion as the field hand with the plow. You cannot be an impostor. You’re not allowed to postpone devotion. Every moment of life must have devotion.
Dazai Osamu, Pandora’s Box
wanzai the creature
Is there a word for this philosophical and life changing (lowk comprehending) view at the age of 15
Why, I wonder, couldn’t he have mentioned that one simple fact… That one fact would probably have settled my feelings, but I was left in a fog.
Dazai Osamu, No Longer Human
Where's Chuuya in the Dadzai AU
ex/situationship/"random" hookup. when dazai tells him he has to take care of the baby he's like "i understand if you want to leave me cause technically we aren't even in a relationship", and chuuya is like "you're crazy for thinking i'm leaving you alone with the baby" but they're actually just very much in love
‘home’
How long do you think Akutugawa would have survived with his lung disease, if not for fukuhichi destroying his neck beforehand?