You're Dazai's and Chuuya's four year old kid. They kept you and their relationship as a secret. Today Dazai was supposed to pick you from kindergarten. He forgot. You wandered around the city and got lost. Atsushi found you and brought you to the agency to help you find your parents. And Dazai walked in

Atsushi: „Hi Dazai-san! Could you help me find the kid's parents?”

You were turned back to Dazai so you couldn't see him yet