In response to some of your arguments about skk being way too toxic and Dazai being too nasty towards Chuuya.
We have only seen Chuuya use corruption once in the primary storyline. Chuuya is a minor character in the main storyline who only appears once in a while to establish Dazai's partnership with him and to set the stage for what Atsushi and Akutagawa can really achieve as a duo.
Basing your entire opinion on a character's dynamic with someone when one of them appears in 80% of the story while the other only appears in 10% is already a flawed tactic. But also note that majority of Dazai and Chuuya's dynamic exists in the supplementary material, which clearly shows Dazai cares for Chuuya in his own weird way and proves that Chuuya liked him a lot less and was a lot harsher in a more direct way.
Lets proceed from their origin as a duo. Dazai and Chuuya meet first in 15 ln where it is made clear that Dazai grew fascinated by Chuuya. Chuuya's first interaction with Dazai was to injure him unprovoked, Dazai is not a morally upstanding person here either and does a lot of questionable things but he is the one initiating physical contact with Chuuya repeatedly, he is the one who jokingly tells him he loves him and responds with a regretful mumble on Chuuya's particularly harsh response.
Dazai is described as having been in awe of Chuuya when he fights, "even Dazai forgot to breathe as he watched the storm that was Chuuya" and this is a pattern that continues in the main manga when we see Dazai watching Chuuya during the Lovecraft fight (his eyes are drawn lighter which is important with Asagiri and Harukawa's work). He then proceeds to remark that Chuuya convinced him to keep living when talking to Rimbaud.
Dazai is shown to be possessive and touchy towards Chuuya from day 1.
This pattern continues with Stormbringer where Dazai is extremely insistent on Chuuya being human and reveals that he is a bit obsessive about him. A few of Dazai's actions end badly for Chuuya in the end, yes, but his end goal was to protect Mori and the mafia at large. But he also gives Chuuya a choice to save his one chance of knowing if he is human for sure even at the risk of Yokohama and everything in it being destroyed. Note that he was pretty much convinced Chuuya would opt out and had already started trying to formulate a plan B. Dazai also caught him in his arms and carried an unconscious Chuuya in his arms all the way to the Old World bar so he could see his friend one last time. Also at one point Chuuya strings him up and basically spins him around in his idea of his most merciful punishment (from a long ass list of them) in retaliation for Dazai's plan which Dazai proceeds to willingly step into and bear because that's their agreement. Skk literally have an agreement where Chuuya is allowed to fuck Dazai's shit up in return for his plans. They are both fucked up people. (Note Dazai decided against committing suicide because it meant nothing could save Chuuya and they would noth end up dying which leads to a long moment of silence and an awkward "wow" from Dazai).
This is followed by Dragon Head Incident where on mocking the death of an executive Chuuya punches Dazai and gets mad at him for making light of loss of human life and Dazai proceeds to make a plan to bring an end to the conflict because, in his own words, 'his partner is cross with him'. Dazai then proceeds to pull Chuuya's head into his lap and stays with him post corruption.
The next time we see them interact chronologically is post defection when Dazai gets himself kidnapped. Its implied that Dazai stayed back in the dungeon to wait for Chuuya as he had already broken out of his cuffs and already knew where to find the data to protect Atsushi, Chuuya quite literally provided him with nothing in that meeting. All we got there from their interaction was Chuuya taking his anger out on Dazai by beating the shit out of him, Dazai and Chuuya's dynamic being established, and evidence that Dazai was a lot more civil and almost friendly with Chuuya than quite literally any of his prior interactions with any of the mafia members he had interacted with on page by that point. They even had a little in joke and this was the firat time Dazai showed genuine and honest joy to that extent on page in the series.
The next time we see them is during the Guild arc where they once again have quite the banter which is once again lighthearted with both of them making jabs at each other, its made more obvious with his prior interaction with Mori beforehand. Yes Dazai ditches Chuuya in the forest but that is literally the only time we see that happen. Letting corruption go on for too long, I mean the fight went on too long too ya'know, Dazai is a lying liar who lies.
The next time we have them work together is in Dead Apple where once again Dazai is not only openly physically affectionate to Chuuya (he held his face even though he had already nullified corruption a few lines ago in the ln) and once again his eyes are at its lightest in the scene. He again sticks around with Chuuya post battle to protect him against his own ability (it is clarified in the novel that Chuuya was not affected by the fog).
After ALL of these events it becomes clear that Dazai does in fact care about Chuuya. Now onto the current arc.
Its incomplete, its ongoing. Why is that important you may ask. Well because we do not know what is gonna happen or how the story will unfold. Let the arc finish before lobbing insults and accusations at characters. Fyodor has already made the remark that Dazai and Chuuya's bond is shallow which is more than likely a set up for future narrative pay off, note that Dazai and Chuuya have always worked with plans that were never discussed with Chuuya picking up on Dazai's clues and cues left specifically for him (the microscope comment in dhc, Chuuya just knowing Dazai will be alive and have a pill in his mouth, Dazai's curious use of the english word good byw in his speech and his whole ass speech in 101). Again we do not know what is going to happen yet so lobbing accusations prematurely leads to flawed analysis.
Setting all of that aside, Dazai's jabs at people are always about what hurts them the most, their most vulnerable parts, their most fragile weaknesses. He hits where it hurts most. The only person in the mafia still alive exempt from that who he has history with is Chuuya whose biggest weakness is his status as a human being and Dazai never insults or attacks his humanity, he always makes jabs at his loyalty, his height, he insults him by reinforcing his humanity by remarking on his most human aspects. Dazai has never been particularly vicious towards Chuuya the way he has been with other people.
The above comment can be translated another way as was done in the stage play.
