This is a single-female-lead story, not a time-travel/invincible tale. Please stop bringing up the early camera thing! The protagonist isn't a time traveler! She's not that close to Misaka Mikoto at the beginning; that plot point will be resolved around chapter 170!
Accelerator: I am the strongest.
Touma Kamijou: Ever since the new neighbors moved in upstairs, I feel like there are more and more things happening around me.
Misaka Mikoto: I'll definitely beat him next time.
Shirai Kuroko: That guy who looks like a mountain, my dear older sister would never like him.
Teacher Xiaomeng: That child? He's really a headache.
Zero: I just want a peaceful campus life. I don't want to cause trouble, but trouble has come knocking on my door. Shouldn't I clean up this mess?