from the word go Hyehin seemed suspect to me. everything was too convenient. her first reprimanding Minzy cause her skirt was too short, then letting her off with a smile. Minzy then finding that weird pic of herself changing in the locker-room among they books. Hyehin informing her, that she put it there and knows who the culprit was... everything just tooo "well timed," one thing falling into a slot after the other. like them then watching Mr. Lee with his polaroid camera - it "smelt" to high heaven -

but u don't get all the answers at once - u notice slowly that Minzy might be infatuated with Hyehin. that's why she's going along with her - blindly. kept wondering why Hyehin target her - cause there a ton of other girls in that class. but it's cause she knows Minzy smitten - easier to manipulate. and that's what all this boils down too. Hyehin using Minzy to get what she wants - back with Mr. Lee? or to start something idk (unsure off that) but for sure, she as smitten with him as Minzy is with her.

the ending is Minzy realizing, she has been used. Hyehin used her from the start to get at / back with Mr. Lee and he folded (either taking her back - or considering/accepting her offer). seeing them together and then to get called back and reprimanded cause of lying. cause Hyehin admitted "they made it all up" - does she blow the whole thing exposing Mr. Lee having affairs with students and why Hyehin suddenly found a "conscience " or what....
but considering her holding the evidence in her hands, there zero options then for the truth to come out - so guess this Not an open ending - and yet frustrating cause u wanna see it through.

interesting movie - love might be the word of the day, but is that the motivation behind every character's actions? in a distorted sort of way, i guess u can say that the motivation behind their actions was love - not the healthy, wholesome kind. and Mr. Lee as good looking as he is, is just a predator that shouldn't be allowed to teach children - no matter their age.