
This anime adaptation is one of the hyped from recent time, most probably because of how good manga is. I wasnt original manga reader, so i will judge this solely as anime watcher.
This anime what i considered as excellent with anime production, especially with its beautiful background & animation quality even in quiet moment. While gorgeous action scenes is kinda expected, the anime kinda push forward with its many of unique camera angles. The characters wise, it have a lot of unique personality that you would love to learn more about their background. The plot also quite interesting, make me wanted to continue watching back to back within 1 day.
This anime is not shounen IMO, more toward dark theme seinen. The story have various of different of "creatures" in the anime, but there arent much explaination aside from several main characters which deal a contract with devil for some power. While there slowburn moment is good to build moment, i think it meant you wont have much plot for this first 12 episodes. Lastly, i think there are several weird thing that i dont think can be explained without spoiling the story, let just say "it doesnt make sense yet".
Excellent anime, something that you just want watch back to back if you have time. Personally i feel like maybe should wait until 2nd season since the first season end with a something build up for bigger arc in the future.