The characters are portrayed in a realistic yet unique way. Bae Joohyun is nowhere near perfect in every way although a plot point is that Soojung is 'supposedly' perfect but again.. not really true. Important characters change as the story goes by, although not terribly. Since the story went fast, there wasn't too much change that occurred. There was a bit, like within Joohyun herself and she was able to even pity Soojung in the end, and loved Jongin and such but not much. There wasn't even a way to dislike Sehun until one point and that was the only point. But it was all done well, so not really complaining.