One day The Beast woke up thinking, “Ah… I’m alive.” He looked around the life he was living in now and thought, “And I am happy.”
Then, if even someone like him, a Beast who knew nothing but death, could learn how to live… then surely, then the man who saved him, who died to protect the dream of his dearest one, had the potential to become happy too.
“I am going to make a new reality.” The Beast declared. “One where he could become a good man too.” And so he picked up a pen and began to write.
The decision to kill Oda Sakunosuke came so easily. He was Dazai’s good man, then it was obvious he should be the one to spark Dazai’s desire to change. And so a promise was made and the timeline began to diverge.
For every loss Dazai experienced, The Beast ensured he would gain something else in return. His friendship with the buraiha was lost, and now in the place of both a good man and the strict glasses wearing friend stood Kunikida Doppo. He had been taking care of his shut-in friend for a long time, surely he was qualified to take care of a suicidal one too?
He lost the familiarity he had with Chuuya now that he had left The Mafia, and now he had gained The Agency which was filled with people who would support and protect him. For every life he killed, he saved many others.
But that wasn’t enough, The Book decided that was not enough. More and more, something enticing, something even more exciting, The Book demanded. The Beast wanted Dazai’s happiness, but The Book was hungry for karma. Soon, ideas started to form in The Beast’s mind, whispered by thousands of realities The Book provided him.
Someone could only become happy if they become a good man. In the end, Oda Sakunosuke became happy in the world where he got to live. In the end, The Armed Detective Agency was filled with happy people! Yes, this was the truth of the world.
The Beast wasn’t happy as The White Reaper, because The Reaper was a bad person.
But the world needed proof that Dazai was a good man. Only then he would be allowed a happy ending. What would it be?
One day, Nakajima Atsushi saved Dazai Osamu from drowning. Yes, this was how this story should progress. Just like how The Beast was saved, then this other version of himself shall be the one to save Dazai. He would become proof of Dazai’s kindness.
And yet the kindness Dazai gave Atsushi--and it was good! it was a good thing- and yet it filled The Beast with nothing but jealousy.
Why? Why weren’t you nice to me? Why him? Why not me? I have always listened to you! He disrespected you now and again! Why him? Why that other me? He wasn’t a good man either!
The Book urged him to write the final confrontation, the climax, that would decide whether Dazai Osamu deserved happiness or not.
The door opened to his residency and The Beast greeted, “Hello Dazai-san. Good to see you again. Have you been enjoying this reality?”
This would be the final test. He would show Dazai the original story, one where Oda Sakunosuke got to live. Then he would present Dazai with the choice to use The Book again, or to go back to the reality where he was loved and supported.
Of course there was a point in this! The pain of remembering would drive people unto the edge, and if he was truly a good man then he wouldn’t hurt Beast over it!
Yes, this was all to reward Dazai.
After all, what reason would The Beast have to hurt the man who saved him?