Hoping I'm not the only one mildly annoyed that her "mental imagination Tadashi" is dark-skinned. Definitely not a dealbreaker, but it's still kinda "wtf".
This chapter may have provided some actually interesting development, assuming that we are to take Tsubaki's statements at face value and that she isn't in fact BSing. (And looking at how ghastly some of her and Tadashi's expressions were in the latter half of the chapter, I don't think she was lying.) She'd still be pretty horrible for her previous attempts - both successful and failed - to get other students and teachers expelled, but the new information takes her from a comically terrible and spoiled teenager who's getting forced onto the path of self-awareness and betterment by a healthy(?) rivalry and reframes her as a cynical young woman who's suffered through multiple attempts to blackmail, abuse, and take advantage of her.
- The previous cases of her assuming that Tadashi MUST fall for her tricks like some filthy horndog suddenly look like far less of a case of an idiot with an overly inflated ego and look a lot more like a teen who assumes that the average man must be like that because she's been harassed by and forced to deal with multiple men who have exhibited the kind of behavior she's come to expect.
- Her "Manhater Prince" persona might not just be her playing an asshole Queen Bee who's far out of the reach of "lesser men"; it may very well be that she's inherently suspicious of men because of past trauma. (Maybe even her boyish-looking haircut is intentional.)
- It also makes her ability to frame students and teachers and make her grandmother get rid of them make sense. Suddenly, Headmaster Granny isn't just some crazy comic book Grand-Karen who believes every last word from her precious little granddaughter and ruins peoples' lives on a whim. She's a woman who's seen her granddaughter be harassed and made the target of abuse multiple times before and errs on the side of caution for her granddaughter's sake, presumably because she'd never think that said granddaughter would lie after being traumatized by such people for real.
- Lastly, it suddenly makes sense why she's so sexually repressed. If previous aggressors made her subconsciously associate "sex" with "animalistic" or even "evil" behavior, then she very obviously is going to want to distance herself from lewd business outside of utilizing various schemes to frame people she doesn't like.
This isn't to really downplay the fact that she's eagerly destroyed multiple careers and even lives and is still attempting to ruin yet another because she hated the people leading them, because that is still fucking terrible no matter how you spin it, and her very status as a butt monkey protagonist who (so far) has basically never triumphed in-story may very well be part of her karma. However, this context gives depth to her, and takes her from an entertainingly terrible girl who is getting forced to grow up to a still entertainingly terrible girl who's getting forced to grow up and is also actually more than a little tragic and broken.
I might be assuming to much from a somewhat salacious manga with more than its fair share of gags, but I think that a lot of things suddenly line up and make sense for more reasons than "because it's funny" when taking the information from this chapter into account.