Erica's eyebrows raised at the mention of secret spies for the teachers. How did he know already? And there were others? She thought that she was the only one. It was after some thought that she realized how stupid she was to not believe that the other Ministry officials would not try the same thing as well. If Perry could do it, what would be stopping the others, including Leiden herself.

"Okay, we can hit the Common Room or the Room of Requirement later."

She turned and tried Pam's suggestion on one particularly nasty piece of stuck niffler. It worked well as the niffler piece started sliding down the wall. Erica grabbed her bucket and started disposing of that gruesome stuff.