This story was, in my opinion, purposefully turned into a parody of office romances.
For example, the actors are totally overacting certain facial expressions for comedy, and the classic employee-and-her domineering-traumatized-child-boss  backstory is also extremely cliche.

And it could have been a brilliant parody considering the cast but parodies are a very hit-or- miss kind of project.
The main actors have shown their ability to portray nuances in multiple other dramas and yet, in this drama, the comedy was very blunt and cringe. This would have been totally fine if it was well directed but the mix between forceful comedy and traditional romance was just not well balanced.

The story is also ridiculous, but here again, it's a choice : The unbelievable trope of the "normal" employee and the domineering almost caricatural boss falling for through unrealistic plot twists , he obviously had a tough childhood and obviously is forced to get married by his grandfather. Very very cliche.

And it could have been an incredible parody if it had that one special element  differentiating the story from other classic office romance dramas.
Brilliantly aligning cliches is not enough to create a satiric story, an off-beat original element was needed.

So all I got was out of this was a LOT of cringe-worthy moments and a little bit of disappointment with how the actor's talent was misused.