It's an open ending, so it's up to us to believe whether it was just Yisan's dream or whether he was between life and death. If he goes through that door, he will regain consciousness, but if he chooses to stay with Duk Im, he die.
I start this drama bcs of the "fantasy" genre. This is the 1st Junho drama I’ve watched, and I kinda like it! I finished it within 1–2 days .imo this drama is honestly not as bad as people said it was.
Yeah, there are some flaws here and there, but for me, it's still ok and they don't really affect the story that much.
Celebrity 
the couple look happy now and then suddenly the FL want to going to Paris at the end? Like...what
I hope they end this well and don’t pull that trope where the FL/ML go somewhre for years and then randomly comes back to reunite
i cry a lott😭
Yeah, there are some flaws here and there, but for me, it's still ok and they don't really affect
the story that much.
team hagi all the way😼