Yuno stops Miyako from falling down the stairs at the apartments, but tears her uniform in the process. Yoshinoya-sensei notices and invites the girls to her room after class to fix it. The next day, having lost her Sketchbook somewhere, Yuno tells Sae and Hiro about the incident with Miyako's dress and what happened when they were invited into Yoshinoya-sensei's "forbidden room"...
