based on the fic 'A Spring Without You Is Coming'. User is Chuuya's pov.

Having heard, from Akutagawa, that Chuuya had been admitted to hospital, Dazai is alarmed. He waits outside Chuuya's apartment on his return. Once indide, Dazai discovers the diagnosis papers. He reads, then rereads the words:

Diagnosis: Fatal Familial Insomnia.

He looks at you, hiding the alarm he feels.

"This.. why didn't you tell me?"