So first thing first, I don't think this is a 'woah, this deserves a daesang' sort of drama, no, it's pretty simple and slow but I kinda like it.
If you are like me and really enjoy a romantic drama without anything dramatic inconveniencing it (ie. mother-in-laws, superficial childhood traumas, family debts where the main lead's family did something wrong to the other, ceo of a company,
unreasonable unforbidden love... the usual) then I think you should give this one a try. Not to say there won't be a reason keeping our main apart, but it will feel reasonable and will be overcome.
Now I know I said it's grounded in reality for a fantasy drama and I stand by it. It's sort of realistic in a sense where the main don't really fight for the stupidest reasons, they are open and honest with each other and their love feels earned. It's nice to watch them enjoy the small things in life, not going after an imminent villain that they have to have a showdown with at the end.

Which leads me to my second point, the lack of an actual villain was really a good thing for me, I know halfway there is the gumiho turned evil spirit but they were only there for half an episode. I like that the fact that the main being a gumiho kept them apart and it felt quite realistic.

But then, without a looming threat to overcome, i think this drama would have been better if it had been shortened. It didn't really need a full 16 episodes, I feel like it would have been better shorter, excluding the whole thing with the evil spirit gumiho. (Also some of the episodes' climaxes were hit in the middle of said episodes ,I'd get up to start a new episode thinking, this is probably gonna be a cliffhanger, only to find out I haven't even finished half of the episode)
It dragged on some episodes that should have been dealt with in 1 episode but stretched into 3 full episode ( the whole Lee Dam acting like she had lost her memory...) and the whole "I'm a gumiho, you're human, we can't be together" thing starts to become very repetitive.

In the end anyways, the supporting characters and the others have good plots on their sides that are interesting and even the main leads are great, they have really good chemistry that make you forget the pacing of the show. The two other supporting roles Do Jaejin and Yang Hyesun are a cute couple in the making and I just loved seeing how expressive Kim Dowan was as Do Jaejin. It's nice to see men allowed to cry on screen.
I also liked the cameos, and although I love Go Kyung Pyo with all my heart but Han Ji Eun and Kang Mina were my favorites (honorable mentions, Jung Somin and Kim Doyeon).

In conclusion if you want to feel fluffy and lonely because you don't have a boyfriend/girlfriend , I recommend this sweet and soft drama, you're just gonna have to deal with the pacing a little bit