The problem with a school you can’t leave that is low-key trying to kill you all the time is “graduation”—i.e., when you have to survive a horde of magical monsters in order to make it to the exit. Those who get eaten don’t graduate. Galadriel (a/k/a El), who specializes in magic of mass destruction, suddenly becomes very popular.
I was so into the story I plowed through this book in less than 24 hours. Strong finish.