@namx2 probably a complex emotion of a top female student?
She's described as the popular girl in the school including ace on p.e and other lessons. Might have scared af when the headmaster appeared and spoke the money (elementary student probably only get around 2000~5000 yen for monthly depending on the family background at that time). Although her behaviour after the blaming only a single person seemed like her frustation (imagined she felt like crap for seeing her crush looked like that cause the girl)
But yeah, I too got confused with that