Is the tsundere archetype outdated? I don't think so.
What happens when Lady Remilia becomes a transfer student and starts her school life? The price is that she loses all her dignity!
School-life comedy (there are no humans left) + urban mystery (crossed out) + industrial-strength sweetness (bring your own insulin).
Related settings are from Touhou Project.
Reader advisory: Congratulations! You've found a terrible novel! This work is the product of the author's delusional imagination. The writing is weak, the plot is bizarre, the logic is chaotic, and the characters are all out of character. Reading this novel may make you feel like you've got kidney stones, so don't let any fanon here get into your head! If you feel uncomfortable, stop reading immediately!
Note: The first two chapters were uploaded at school in 2023. The content after that is a cyber-restoration of a cultural relic (see the end of Chapter 3 for details).