basically fyodor is obsessed with dazai's ability to nullify other abilities, after encountering him for the first time. so when he meets dazai again at the hospital he makes it his life goal to get dazai out of the mafia to join him. and dazai who got into the hospital after a svicide attempt accidentally met him whilst trying to leave the hospital without being caught, so it's a fyozai ship but at this time dazai is 17 a year before odasaku dies and fyodor is 21 so there is NO smvt:3