This should've probably been better as say 4-5 volumes than 10+ volumes. The story starts to seem too long, and we're waiting and waiting to find out who the King is, although there is a lot of foreshadowing and random action.
Tsubasa's lack of interest in the boys around her was surprising, especially her little boy buddy who breaks laws to help her investigate. And the boys are the ones who are really doing the work, although Tsubasa is taking the risks... which endlessly backfires and she needs saving.
And twins
hating each other to the point of trying to kill the other
was kind of interesting... although
! the boyfriend was probably the biggest surprise, and I mean his cheating ways among other things.
Regardless, this is not a manhwa sitch where the rowdy twin gets her man and overpowers the school with sheer strength and character (if you read manhwa, you know what I mean), but it feels similar in that respect. Better plotted, more controlled, but similar.
There was a comment about adults being almost completely absent from the comic, and that's true. Where are the teachers and parents in all this? Isn't anyone paying attention to the number of injuries and deaths in that class? Sheesh.
So, if you're looking for something that's shoujo-ish in looks and nature, but has a mystery-thriller type plot, this might be your manga. But, really, there are much better mystery-thriller manga out there. If you're hard up to kill some time, give it a try. But I still think it's too long, and would've done better to have been cut in half...