tl;dr: A messy and generic cyberpunk ninja manga. This is the manga adaptation of a novel series about a ninja’s fight against a criminal organization in a cyberpunk version of Japan. The manga begins by showing how the protagonist was originally just a salaryman, but that after his wife and child were killed as a result of simply being in the wrong place at the wrong time in the middle of an operation by the Soukai Syndicate, he made it his life’s goal to destroy them. This is where the manga gets a bit messy. It fast forwards a year into the future at which pointthe protagonist is now known as Ninja Slayer and is an incredibly powerful ninja that the Soukai Syndicate is after. You can pick up a lot of what’s going on from context, but it doesn’t really explain anything properly so it isn’t really clear at all how things got to this point or what is going on exactly.

At the end of the first volume it goes back to right after the protagonist’s family was killed. The rest of the manga is basically filling in the gap that the original time skip created. It shows how the protagonist is possessed by what is referred to as a Ninja Soul. It’s never quite made clear what that is or how it works exactly, but in essence if he allows it to take control of his body, he gains incredibly powerful ninja abilities, but he loses his humanity and starts mindlessly killing everyone around him. The story mainly involves him fighting against various ninja from the Soukai Syndicate while ensuring he stays in control. Along the way he gains a few allies, mainly a ninja sensei that teaches him techniques that he can use so as to rely on his Ninja Soul less, and a hacker that helps him deal with the cyber parts of the cyberpunk setting.

All in all, I found it all really generic. There isn’t really anything unique or particularly interesting about the cyberpunk setting. It’s basically just the standard stuff like high income inequality leading to a class of people that are treated as trash, corporate syndicates that have more power than the government, and cybernetic implants and modifications that make all sorts of superhumans. This manga leans towards being battle shounen so all of that is used as a framework for intense fights between people with wild powers. But it’s not particularly good at action either as the fighters and their abilities aren’t that well fleshed out. The cast overall is very flat without any depth to any of them. I also don’t find the art all that impressive as it was often trying to go for rule of cool, but only rarely succeeded. Combine that with how the plot is incredibly simplistic and even then doesn’t make any progress at all due to the strange structure, and the end result is a manga that’s mostly just dull and unsatisfying.