It started out really well but now the story is becoming ridiculous. The letters were a big part of the story but it seemed like they just shrugged it off? Also, why are the 2 main characters written that way? Seo Dal Mi is so hellbent on winning against her sister. Nam Do San is the same with Han Ji Pyeong. He doesn't want plan B but ends up asking for HJP's help (aftter beating him up)?!?
If Han Ji Pyeong wasn't in this, I wouldn't even be watching this anymore. That character deserves better!
Update:
Watch if you want to see Han Ji Pyeong and how good of a character he is! But if you're looking for a good story and something that's fresh, don't watch. You're not gonna find it here. It's just another cliche k-drama. The actresses and actors were great tho! But the story, naaah.