First thing i have to mention is that the 3/4 last dramas of Park Min Young have been literally the same, it feels like I have watched her portraying the same exact characters but with different male leads ( what's wrong with secretary Kim, Forecasting Love and weather, Her Private Life...) she is completely stuck with the roles she picks and that doesn't allow me to see how she actually performs ( if she can)
The concept of the series is somewhat original but feels more like a modern version geisha or gisaeng stories ( like when in the past they would literally kidnap and breed girls to be the perfect submissive male companions. Yet somehow in a modern society it doesn't work well and there's too many things and wholes that makes zero sense.
I am not a fan of love triangles ( usually) but sometimes if its well done and the script is well written, it does work and you end up suffering wanting to know what happens and who will be the triumphant ending couple.
This is not the case in the majority of kdramas unfortunately, including this one.
The love triangle here is just causing underdeveloped characters, and storylines left halfway. There's not enough time in the show to deepen into the layers of the main characters and you can't even get invested enough with the secondary lead either for the same reason.
If you ignore everything around the main story and just focus on the development of the main couple you will be able to enjoy their chemistry, its good enough to keep you entertained for a few hours, just don't try to think of it as a smart story that makes sense.