"Why do you like me?" the young Shizuko (Go Won-hee) flirtatiously asks her dorm mate Yeon-duk (Park So-dam) at the all-girls boarding school where both are enrolled. "Because you're weak" is the first reply. When that doesn't suffice, "because you're weird" is the next rejoinder. I like this train of thinking. It makes sense to me! Because there is something appealing in someone who needs you (as suggested by the first answer) as well as in someone who entertains you (as suggested by the second one). The phrasing may leave something to be desired but when you ask a question like that, you deserve an answer with a little sting.
Shizuko doesn't mind the sass. At this "last chance" school where everyone's reputedly sick with something, the healthier girls are sometimes bullies. A friend who's tough is a valued commodity. As far as she herself knows, Shizuko's only crimes are having the same name as a previous student (who mysteriously) disappeared and coughing up blood (when stressed). Are those reasons to hate someone? They are to Yuka (Kong Ye-ji) who desperately wants to escape this place with its Japanese military training and creepy head mistress (Uhm Ji-won), and win a scholarship to Tokyo. You can't blame her either. After all, wouldn't you be leery of staying someplace where they fed you pills all the time and hooked you up to an IV needle for a special vitamin? What if you found out those treatments were giving you superpowers? What if those superpowers came with side effects? What if those superpowers weren't guaranteed? Tough questions, right? No one said that school would be easy.
And that goes for the staff, too. One of the counselors (Park Sung-yeon) is subjected to quite a few admonishing slaps while the one male employee (Sim Hee-seop) clearly has issues with taking orders from a woman. Well, pain is a great teacher. For pleasure, a long-stemmed cigarette holder will be provided. In The Silenced at least.