「ネタばらしするとだな」っと… ネタ has to do with jokes and foolery, but I'm not quite clear on how its directed and thus how it affects the thrust of this line...
Is it that she feels like she should be responding to this as an opening for 突っ込み? Or is it more like she feels she's being made the butt of a joke? (Or am I off base completely?)
Koakuma-sensei appears ★...Hmm, well, it's a little revealing...Clatter!Is it okay to come out?Are you an idol?Huh?Nice to meet you, too...Eh...?
It's not Moko-tan?Well, well, I'm the special teacher for today's lesson......but I actually I called Patchouli-sensei the manga artist...Nice to meet you ♪It's okay!