What's happened here is that Kogasa has just guilted herself into working the next one. It would be kind of awkward to answer that question with "No, and I'm not really staff on this one either", after just being exposed to behind the scenes gossip she shouldn't have heard while eating a staff lunch.
Of course, given that Kogasa is the author's self-insert character, these strips are pretty much letting the secret out.
Tousan Festival staff lunch roomAh, by the way, are you going to be on staff next time as well, Kogasa?That 〇〇-san from the 〇〇 convention...WaaaaaaWhoo-hoo! You betcha!♡Everyone had a good 〇〇!So, what 〇〇 did was...Ain't No EscapePerspire
SweatYou know what?...used 〇〇 to 〇〇 and ended up being 〇〇ed!Wh..What should I do....I think I just heard something really bad I shouldn't have heard...BwahaSweat
Drip