The next chapter is "it".
Either it's your regular anime BS with girl standing up, smirking and saying "I knew you're going to punch me in the face, good thing I made my face especially hard so it absorbed all the impact".
Or she actually just being unconscious.
99 % it's the first, coming from Kakegurui I don't expect some great level of writing and realism here (only when it comes to Majo Taisen, there, for some reason, the author shines, maybe because it's literally magic BS)
Like I am sorry okay, highschool girl beating up thugs, basically experienced in fights men, already a huge stretch, but for the fun of it sure, but a highschool girl beating up MMA fighter... only if she's possessed by Mike Tyson or Bruce Lee.
The regular Tyson, not the one who "fought" Logan Paul