If I were to rate this considering only the horror storyline, this is a solid 4 or 5 stars. It is really a good story but fucking mlm fetishizers should stop glorifying the relationship with Bum and Sangwoo. They're not meant to be romantic nor a normal couple, they're both horror characters on a horror setting. The BL categorization is also playing part on the horror so, NO, it's not a love story. It is a very great narrative of trauma, SA, Borderline, Stockholm/Lime Syndrome, murder and psychological thriller. The fact that these dudes had sex doesn't justify any of the other stuff mentioned.
With that out of the picture, great manwha. Koogi is really a smart author.
Killing Stalking