If you are looking for a supernatural romance, this might not be it BUT

It has leads (and supporting characters) with great chemistry who goes on supernatural adventures. It is a story exploring human relationships and actions.
If you are still hesitant, I say, just do it.
Why should you watch it:
1) It is really refreshing to have a female character who is strong.
Not just the type of 'strong' that dissipates because the plot requires the male lead to come and save the damsel kind of 'strong'. Of course, throughout the story, both Ji Ah and In Beom save each other many times, but it didn't feel forced. The circumstances made sense with each of their core characteristics and plot development.
p.s The Female characters are not annoying and quite likeable.

2) The characters in the different cases are presented fantastically.
They feel real and bring resonance and sympathy as the story unravels. Even though they are dealing with these scary ghosts, it makes you wonder if ghosts are really the most scary things. Is it the people, the actions, the society or just your own regrets.

3) This is NOT as dark as it might look.
Even though it discusses things about regrets, society, crime and GHOSTS, it feels like it is a discussion and a comment rather than a deep dive. (This might be good for some or bad for some people). It doesn't aim to make you feel depressed or give you feelings of atmosphere of oppression (e.g. strangers from hell). The overall outlook of the show is positive.

Last but not least
4) Well paced
The pacing feels good. If there is a problem, it is usually sorted out quite quickly. It doesn't feel draggy.

Critiques:
There isn't much negatives. If you are super logical and a realist, maybe there are something that might you might be able to nit pick. However, it is not aimed to be a serious crime drama so it is acceptable. It will not disturb you viewing experience.

Final Note:
I really appreciate that The romance is not forced, I think it is good to see the different relationships between all the key characters and how they care and look out for one another. If you do decide to watch it, happy drama watching!

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