Art - Goth's art is simple but pleasing to look at. I quite enjoyed it and to me it's what carried the manga.
As for story, the premise seemed to be very strong right up until it was revealed their homeroom teacher was the hand killer. After that point the story well down a whole of cliché tropes and edginess, shit was corny. It's very unfortunate that this one didn't turn out to be good and a great teller was just some of the dialogue between characters, just very still and incohesive. character motivations were incredibly lacking as well. Just not very well written. Sucks.