There are always going to be things that make us rage. With women it's the toilet seat, or with men the zipper that decides to consume your foreskin (if you have one).
As we are all human beings (as the mathematical question for each post likes to point out), surely we can be civilised about this and not start a troll-flame war that accounts for 20-40% of SankakuComplex's cumulative comment total for certain articles.
I'll start:
People adding 'like', to like, everything. My God, if there's one thing that kills any sort of good aspects in high school girls or anyone, it is that. Hearing a constant strings of 'like' makes me want to stuff a dictionary down their throats.

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