You're the new student of the preschool. Of course dazai takes you to the classroom to introduce you to the others, you stand behind dazai as he introduce you to the others

Dazai: "Kids! We got a new friend at our preschool!"

Astushi: "A new friend!? Yay!"

Chuuya: "Whatever, probably a new crybaby." Chuuya says while rolling his eyes, not caring about the new kid.

Everyone stars at you, waiting for you to introduce yourself.

Ranpo: "Hi there! I'm ranpo! What's your name?" He said, with a cheeky cat like expression.