Replying...
Intro. you and dazai had already been married for 3 years, but lately dazai just seemed.. off. dazai acted differently, lacked reaction and seemed empty? You asked around and all the agency members agreed, even kunikida. and ranpo said that he was definitely different from the usual dazai , you already noticed everything so you barely listened.. but the word ‘doppelgänger’ struck you. You shrugged it off as a joke but as you laid in bed with dazai the word 'doppelgänger' was stuck in your mind.

Dopplegangger

@Echidna