For anyone else confused about the plot like I am, I think this is what’s going but please feel free to correct me also SPOILER WARNING, if you’re not caught up:
Hell is in a middle of a civil war where they’ve split between the north and south. The north is controlled by satan and the south is controlled by Cain. Each have their troops and they occasionally engage in fights such as the one that Cain was in where he got shot by Satan and injured. Due to this injury he’s been weakened so he’s looking for the doctor guy to help remove the bullet from his chest which he sends Sid to do with his compass relic but Sid seems to have his own motivations. At some point Cain questions his loyalty but ultimately decides to trust him again but with the threat of death if he betrays him again. Gyeong joon was marked as Cains door (why or how idk) which is why the cultist dudes were trying to kill him in the beginning (or honestly it might have just been coincidence lol) and Cain saved him. I think they were trying to kill him to prevent Cain from being able to return to hell. When a demon marks a human as their door the human gets a tattoo that has the demons name inscribed so that other demons know which demon they belong to and killing a demons door could potentially trap them in the human realm because if they are unable to make a new door before their current door dies they can’t transfer the mark. I think some humans are able to withstand being a door better than others it seems to be inferred that gyeon joon is a particularly strong host and being Cain’s door in particular draws a lot of attention from his enemies. Gyeon joon is investigating the cultists since they're committing crimes across the city but what is later revealed is that they have the door tattoos but no demons names inscribed to them I believe the pink hair dude who was just introduced is the one doing it. I’m not 100% sure what his motivation is and I think Sid is a double agent since he was working with the weird bondage dude to kill the doctor so Cain stays weakened but the bondage dude didn’t realize the doctor has multiple clones and only killed one of his clones not the real doctor.
That’s what I’ve gotten so far feel free to add smth I might have left out. I like this webtoon the art is so great and I like the action but the story is kind of difficult to follow lol ┑( ̄Д  ̄)┍
1st story: cute, kind of questionable at the second chapter but overall cute ending
2nd story: could have been a funny mix up kind of deal but the seme was a total creep
3rd story: electric chair
4th story: eh...
Electric chair