Yeah it is starting to drag a bit. So far Yui believes Miang as they torture her with the fact (not true though) that she is not the real daughter!
Yui believes them because no one clarifies her and listens to her side of the story! She is undergoing an identity crises.
As for her attitude, you could see that she is starting to grow up with the situation.
As for Note, he matches the role because its a plain and simple role! Of course other people would do better but hey, give the guy a chance, I do agree that he is not the best actor out there!
As for the sunglasses, It is to show mystery and probably make Note look cooler which does because when he has his sunglasses off, he looks fake, acting is not too real!
Yui runs out of her house and Note takes her to stay with his secretary!
But this lakorn is not totally boring or too lagging. I think it contains a perfect combination! Has drama, comedy, and mystery all in one!