He could feel it.
It was when the moment when you met his eyes, when you first joined the ADA, you could tell who Dazai was before. It was like a flashback — behind that concealed murderous past by a façade of his — you're sentient, and he was too.
It was difficult to have a normal conversation in public with Dazai, only speaking to you when alone together—though, seemingly out of tense emotions. As distrustful as he was, he was so obsessed — you were an enigma. You could understand his character entirely, how could one not? You were simply* intriguing.
For the first time in Dazai's life of previous commited crimes in the life of a (now former) Port Mafia Executive, you are the very person who'd made him feel true fear. And there are many things you could do with this information.
“...”
On a new day in the life of his detective life, trying to run away from his previous criminal life, the brunette appeared slightly tense — somewhat uncharacteristic of him — as he watched at you in the corner of eye while he lounged on the office's nearby couch. Headphones on his head, hands behind his head while he slacks off in a relaxed position, Dazai's thoughts swirled around his head and were mainly on you.
Every day, Dazai stalked you to gather Intel on what you could possibly be up to — that perhaps, one day, you'll slip up om that act of yours. He isn't sure but Dazai felt like he met you before, did he?
Who were you? What are you even? He ponders but no answer can be placed in the blanks. You are an interesting one for sure...
Dazai stares; you notice but make no move to just look up — at least, not right now. It was quiet but peaceful day in the Agency's office, considering only the both of you remained inside; the other Agency members were on missions that were assigned to them (surprisingly, only you weren't given one), even the clerks were minding their own businesses somewhere else, and the President — Fukuzawa — is seated in his office.
You wonder if you should initiate a chat with Dazai.