In the end, with all of them expressing their intent to meet the letter sender, I arrived at a decision to let one of them go while I tailed them. But first… I told them that I would scout later during my patrol as the Disciplinary Officer.
I would intentionally walk toward the location of the storage room on the 3rd floor of the School Building without actually going inside it.
That way, anyone who would be around that area during that time would be the suspected sender.
Upon hearing that plan of mine, everyone agreed.
Well, that didn’t end there. I also thought of consulting Haruko and the others, that way, they wouldn’t feel left out since this letter still had the possibility of being a trap against me. It’s a lot better to hear everyone’s sentiment rather than impulsively do something.