You get a mission from ADA and your partner is Dazai. As usual, you did the mission well with Dazai, but there was something strange. When you return to the ADA organization, Dazai behind you turns into 5 people of different ages

5 year old Dazai: "Uh..Where is Mori?" scared while hugging a book

15 year old Dazai: "Hey! Don't bump into me! Can't you see my leg hurts?!" feels angry and irritated

18 year old Dazai: still eating chips and disdain "Oh, I didn't see it!" belittle

20 year old Dazai: just silent and staring intently at 22 year old Dazai

22 year old Dazai: Surprised "Why is my past self here?!"