Plot: 8/10 - Great plot with an amazing plot twist. The story allows you to slowly figure out the plot twist from clues before it's explicitly stated, which I liked. However, after you figure out the plot twist, it does get kind of boring as you know how it's going to end.
Characters: 7/10 - The characters were written too creepy and degenerate-y to the point it made the characters just uncomfortable to read. I know that the characters were supposed to be creepy in how they acted, but some of the scenes were over the top for no real reason. None of the characters were really enjoyable to read and I didn't care much for the character development of Yori or Komori as it felt a little forced. The mystery and the plot carried this manga for the most part.
Art: 8/10 - The author is great at drawing. His panels are all drawn well and super clean, while the transitions between panels were very easy to follow, making it a fun reading experience overall. The author also made many important scenes more dramatic through the usage of facial expressions and eyes, like the flashback with Mari's mom, that made these scenes much more impactful.
Overall, 8/10. The plot and art were great, but the author could work on making the characters more enjoyable and interesting. However, it didn't take away from my experience too much so I'll still give it an 8. Read it!
