There is no chemistry between the lead actors; this isn't the first series of his that I've watched. I don't know if it's his acting in general, but romance isn't his strong suit. He's unconvincing and seems clueless about how to portray love in his performance.

Beyond the couple's scenes, most of the scenes are really boring, lacking spirit. The plot is dull, but so are the supporting characters and everything else.

There was one beautiful scene of his confession and forgiveness towards her, but it didn't take off in the end and just fizzled out.

The filming space for the entire series is cramped. The apartment is small, and it continuously shifts between boxes and faces closeup, which is unconvincing and even creates a sense of frustration.
Progresses slowly and in an unsatisfactory manner without any excitement or emotion.

The ending is also frustrating in an unusual way, making you wonder why you watched this series in the first place. It's drama over nothing.