Y’all I promise the story makes sense, there’s just a long time between uploads 😭�...

Please can you explain to me i don’t mind spoilers

So basically, after Reapers friend destroyed the life stone of whatever it’s called, Seowoo kept getting out of control (The whole “let’s go somewhere heavenly” thing.) the amount of time in between each refill would get shorter and he needed more and more to keep him sane.
SeoWoo realized this and told the reaper to just let him pass into the afterlife but reaper obviously didn’t want to do that so he made a plan to go into the underworld to steal another artifact that could provide the same purpose as the broken necklace. Seowoo realized this and asked if he could go with.
When they got to the underworld! Seowoo, being alive and all, had to take some extra precautions to not get caught bc his scent would give him away and that would cause a bunch of extra trouble, however the person that reaper had contacted for help was already with King Kang (sorry I don’t remember if that’s his name lol) one of the leaders of the underworld.
He found it pretty amusing and after Seowoo and reaper got separated (reaper had gone to where they were keeping the sacred artifacts), he went to Seowoo forced a drink with him and revealed that he knew the plan all along.
However while they were talking, reaper got caught in one of the artifacts, a mirror, and not just any mirror, one that’ll put them into a dream state, one that brings them back to their past life, before they died. And if the reaper doesn’t realize he’s in a dream, then he’ll get lost in the mirror and seize to exist
So king Kane gave Seowoo the task of getting him back, at the expense of his own life bc if Reaper didn’t remember then Seowoo would die in the mirror too. Obviously Seowoo went after him and to help him, King Kang gave him an artifact that would help him in his journey, a bell.

When Seowoo entered the mirror, he found himself in an older Korea, (idk Korean time periods, but think thousands of years ago before industrialization lol) and he pretty immediately found reaper but the reaper thought he was a demon as seowoo appeared out of no where, but the reaper was a kind hearted man and couldn’t let him sleep outside alone so the reaper took him in.
Basically the only way that seowoo was gonna help the reaper realize that he wasn’t in a dream was to help the reaper through his past trauma. And the trauma was saving the village/manor/castle he was staying at and its people, since we learn that in real life when this happened, everyone died in the fire.
I don’t feel like explaining what all happened in the mirror but Seowoo ended up saving everyone with the bell that King Kang gave him as it sucked up the fire and allowed everyone to escape. After that event reaper realized that it was a dream and they walked out the mirror together. When they came back, Seowoo had sustained severe burns from inside the mirror and it will even show up when he gets reincarnated. King Kang even gave them a new necklace.