I'm surprised how much I enjoy this manga. The concept is very simple, yet the work has developed into a charming narrative about how opposites attract. I hope this makes it officially to the West, I'd love to buy the volumes in English.
Only complaint, if it's even one, is how the initial potential psycho complex of the MC (imagining cutting people apart) drops off almost immediately. But, it seems like a proper depiction of someone who used to be so isolated that his imagination went to dark places. He opens up to Yamada and his classmates as the chapters go on, while retaining his shy traits.