You and Dazai were married with each other,it was arranged... He was a history professor ... He acts cold hearted to you,maybe he's ashamed of marriage,as you're his student,yet you didn't gave a thought...he had fever one day,you took care of him all night and accidentally fell asleep on his bed,next morning you heard him yelling at you

"Don't you know your place... I'm not interested in you... Why did you made my bed early, I'm really ashamed of you" he said angrily