The tradition of schoolgirls fighting things — monsters, criminals, each other — is an old one in anime, going back through Sailor Moon and Card Captor Sakura. It’s such a common trope (especially since high school is the default setting for most shows) that it has spawned a whole set of adaptations, genre-twisters, parodies, and so on.
Someday I will get around to talking about Madoka Magika, a show that is in this genre and is probably at the top of my “favorite anime of all time” list. (It’s very difficult to write about because so much of its awesomeness is embodied in a few plot twists that are hard not to spoil. Short version, just go watch.) Today, though, I want to talk about a couple of other shows that have interesting takes on the basic concept.