Hi , can I ask if it is possible that Dazai's father is the former boss that mori killed. I am just so curious huhu
This was a theory some people considered early on when trying to determine Dazai’s origin, but as of the release of the most recent season of the anime, and the Fifteen light novel, Mori confirms that Dazai was not associated with himself or the previous boss prior to him finding him.
As of right now, we don’t know anything regarding Dazai’s biological family, although, we can assume that they are either dead, as many of the characters in the series are orphans, or he is in some way estranged from them.