Plot-wise these two have pretty much nothing in common. If you enjoy the acting of the female lead on the other you will enjoy the acting in the other one too. I personally found the female leads pretty similar with their over-acting characters and tacky clothing. They're similar to the point I would think they're siblings.
Yamashita Kotaro was living a peaceful life as a publisher part-timer aspiring to be a mobile phone novelist until two females suddenly appeared in his life. One is his six-year-old celebrity niece and the other is the little girl's stern manager. As he is forced to live under the same roof as the little prodigy, their differences soon manifest and disputes ensue. However, through co-habitation, Yamashita slowly comes to appreciate having a family and the warmth it brings, all the while developing a love-hate relationship with Fuji Mineko, the manager.
The core theme of both stories is the same: The female protagonist possesses a vibrant personality and relies on her intelligence to survive. In different scenarios, she assumes the role of a close relative of the strict male lead. Initially, they have a competitive relationship, but gradually they develop feelings for one another. Furthermore, a second male character, an apparently perfect individual, appears as a supporting lead in both storylines.
Both have the same writers (Hong Sisters) and even though the stories seem to be quite different you will realize that they have some points in common. For example: Like Joong Won, Seol Gong Chan is a CEO (but a hotel instead of a shopping mall)& acts cold towards the female lead but is willing to help her later on,in both the female lead keeps annoying the male lead in the beginning. Female lead feels lonely in both. I can't think of other similarities right now (And I don't want to spoil it for you).You will see while watching :)



