Sincerely, I'm dissapointed with the low score it got.
Long story short: it's a slice of life drama with comic scenes and some really good life lessons
The only reason I see for the low score is that people came with expectations of something else (even after the first episode), being a kdrama wanted more drama(but it isn't that overdramatic type) or didn't finish it.

Gave it an 9.5 score and I would recommend it to watch to someone that wants a light rom-com without exagerated drama or complicated storyline. The only thing exagerated are the effects of the fight scenes, but if you want a light show to watch it's as good as it can get.
The only reason I didn't gave it a 10 is subjective, like most opinions posted in reviews, and that's because of little things that I didn't like, but I still binged most of it.

Conclusion: Give it a try!