It was a boring mess. I never warmed up to the ML and I preferred Si Yeol much over him. The mystery part was way over the top in the first half of the drama. It was obvious what the writers wanted you to believe - so many obvious (and weird) red herrings. The FL was bland with no other characteristics than being kind.
For the first half, it felt like the writers added the romance as an afterthought while in the second half, they completely threw any mystery out of the window. Even with the mystery it was bland but without it, there was nothing to it anymore.
While it was very mid and hollow throughout, I was hoping that at least the ending would be satisfying but it was disappointing. Important motives were changed, characters blamed other characters for stuff that doesn't make sense and in the end, I had the feeling they could've just completely left ML out of the story and it would've had the same outcome.
I'm really disappointed in the story writing but the soundtrack, colours and production quality was really good. Wish they would've casted actors with more chemistry and hired better scriptwriters. Missed opportunity because the idea has potential.