As we all know AI can't make something creatively original, it picks up different things mashes them together and gives out "art" whether it's pictures or writings. This drama feels like that. It's just a mashup of other popular fantasy dramas and even then it suffers from many plot holes. Add to this the laughably bad acting of the male lead in comedic scenes.
This drama has everything;
Bad story
Plot holes
Bad casting
Bad acting
Cringy comedy
The only good things about this drama are the music and the visual production.

It would've been a bit better if they had made the demon character a little more serious because Song Kang is good at play serious roles.