Because she isn't a tsundere. She's just a narcissistic asshole who is excusing her own horrible Behavior. She doesn't actually like him, but rather she feels like she owns him and he belongs to her.Even someone who love tsunderes (who are usually unreasonable), like me, thinks she need a slap, at the very least.
Bro just make a plot "well actually u are the bad person" i didn't show it anywhere and just the opposite but yeah the MC is badwI gotta ask if the author remembered what happened in their own series? Did they get amnesia at some point while writing the last 2 chapters?
Communication is important, but what's even more important is dropping your ego and your tsundere act. Good thing MC here kept a cool head, even though he was mad in the previous chapter
Looking back at it, while his confession to someone else does indeed seem to have been the trigger, it sounds like he'd been blowing Hyouka off and prioritizing this other girl for a while, given "That again!? You've been really distant lately!" on Page 2. (Yes, he says "Just for today, okay?" on Page 3, but we've all seen enough anime and read enough manga to know this is frequently used in situations where issues have been running for longer than just one day.) This doesn't excuse any irrational anger she has over him not being a mind-reader, but if he really had been focusing on this other girl while canceling plans with Hyouka, then that portion of her anger is justified, especially if he tried to rebound right back to her the next day like nothing happened, as the bottom of page 29 of this chapter suggests.According to Chapter 1, the inciting event was apparently him confessing to a girl he liked. I wonder how the writer intends to justify that being a reasonable enough offense for her to completely change and treat him like garbage. Yeah, sure, her feelings were hurt because he didn't confess to her instead, but that's her own fault for not pursuing anything more than friendship.