[Mad Pierrot]

I caught up to the series following the third season's ending.

Spoiler for what the?:

So Fyodor somehow arranged his own imprisonment rather than being caught by Dazai. In prison, Fyodor causes his underlings to make use of the famous book in order to cause a big chaos to the agency. The story then starts giving some twists and because the current arc is not finished, I can see why season 3 ended like that.