Obtained: During the Chapter 4 Intermission, Maiko will send you a Topic. Read it then travel to Fortuna Office and speak with her.
She’s drunk again and wants us to reorganize things in the box at her feet. “Check” the box and start organizing! As you select each item, a cutscene will trigger and Maiko will give you a back story of the item. When you are done with all the items, a brief cutscene will trigger and the side story will complete.