First, this show is better than other Korean dramas (in my opinion) so having said that I'm going to point out the parts of this show I didn't like.
It started off humorous and different to other Korean shows, then they had to inject the dramatic, romantic unrequited love bits which I guess is just a must have.
Also, I understand that the assistant is supposed to be this likable humble good hearted girl, however, she is too annoying! At around episode 7 I couldn't really handle her anymore. She has an astonished expression and a look of disbelief way too often.
i.e. boss: "go get me a pen and paper"
assistant: "What? Who me?"
boss: "Go check the messages"
assistant: "What? Who me?"
boss: "I called because I was bored"
assistant: "what? Who me?"
I think her level of incredulity needs to diminish over the development of the show.
I feel like the script writers were lazy and didn't want to make her character more complex. They stage her character as "really dumb", a fact reinforced by her boss but even more credible when her father says it too. So, if we're watching a really dumb girl doing dumb things, how could it not get annoying!
Granted, she starts to learn (slowly) and surprises her boss occasionally. Yet, I wanted her to move along with that momentum and mature more quickly.
I feel you - I hate main girls like that... Just because they're innocent, nice, kind, etc. doesn't mean they have to have missed the brain boat completely.