Blind Play
Don't even know what the point of this story is. It certainly isn't romance, and I'm not seeing a setup for a psychological study of the human mind here either. So that leaves... sexualizing mass-murder and rape... yeah I'm out. Disgusting story, disgusting author. Dropped and regretting ever reading a single chapter.
The Beast Must Die
The story is interesting and definitely stands out among the crowd, but the writing is kind of lacking. Certain plot points feel really rushed, e.g. how the whole mystery and revenge plot is solved half-way through the webtoon in only a handful of chapters. And we don't get enough background on the characters to really sympathize with them. An example of this is how we don't really learn about the sister's trauma, her relationship to the MC or even just how her face looks like before the initiation ritual, which makes it harder to sympathize with his decision to go through with it.
Killing Stalking