I like Enta Shiho's art, but all these covers with just a girl's face looking at the camera all feel kinda samey after a while...
People probably didn't quite expect the zombie virus to take over the world in this way. Twenty years have passed since the first recorded instance of a "zombie" or the "living dead." With time, scientists discovered it was not a virus, but a pathogen that causes dead mammals to becoming moving creatures again, even though people still commonly refer to it as the zombie virus. By now, most mammals across the world have already been infected by the pahtogen, but fortunately, a healthy person (or animal) usually has enough natural resistance against the zombie virus. It was when they die, or are severely weakened, the zombie virus can take over their mind, controlling the living dead. While the pathogen only affects the recently deceased (older bodies have not risen from their graves), society had to adapt to a world where the dead, and also the critically injured and ill will turn into a zombie. Many of them of the human zombies are rounded up, but because it is impossible to tell which are zombies of actually dead people, and which zombies are of people who are technically alive, but taken over by the zombie virus, they can't really "get rid of them" that easily. The bigger problem is the food economy, as it became impossible to do factory farming anymore, as even one single sick animal could in no time tun all the others in the farm into zombies. Society had to adapt to the new reality, and to some extent, they did, but there is still much to learn about the living dead.
Ultimate Medical is a medical company doing research into the living dead, and one day, they have a big announcement to make regarding zombie research. The presentation is to be held at the manor of Ukari Ichirou, an executive of the company. But when the time of the presentation arrives, the scientist in charge doesn't appear on stage. They go to the room where he was preparing for his presentation, but find it not only locked from the inside, but they hear rather worriying grunting noises from inside. When they mange to open the door, they see what they had feared most: the glassy look in the eyes and the slow movements of the scientist as he charges in the direction of the humans is unmistakable. The scientist is eventually led out of the house, where the police manage to capture him, but they are confronted with a mystery: the scientist was clearly murdered, which turned him into a zombie, but the room where he was preparing was completely locked from the inside, door and windows, and no weapon was found in the room, nor a murderer. So how did the scientist turn into a zombie? Yatsugashira Ruri, a rather young-looking detective, suddenly appears on the scene and manages to convince Ukari to hire her to find out why the scientist was murdered and how, but it doesn't take long for Ruri to get targeted herself by someone, sparking the suspicion that something bigger might be going on. Will she figure out who the murderer is in Kobayashi Yasumi's Wazawaza Zombie wo Korosu Ningen Nante Inai (2021), or as the cover also says: No One Bothers to Kill the Living Dead?A mystery about the living dead might not sound that original anymore (because of exhibit A and exhibit B), but hey, it's a book by Kobayashi who makes really great use of supernatural settings in his mysteries with his Märchen Murder series, so if there's someone who can come up with something cool with zombies, it must be Kobayashi. And certainly, if there's one thing this book absolutely excels at, is the depiction of a world where a zombie virus (technically not a virus) has taken over the world, but not in a way that has immediately caused the downfall of human society. We are shown "zombie farms" where zombies are rounded up and just... let free, because they don't really know what to do with them, we have detailed descriptions of how the food economy had to change because it became impossible to continue the large-scale farming model and other goosebump-invoking details like how with the changing food economy, some people started to enjoy zombie meat (because it's better than nothing) and some even very much like the suspicious "monkey" meat they sell of which everybody knows it's not a monkey but they want to lie to themselves, and some people even go out hunting for wild zombies themselves to get some... fresh meat right off the bone. The world-building in Wazawaza Zombie wo Korosu Ningen Nante Inai is really interesting, and in that way, quite different from the earlier mentioned examples of zombie mystery fiction, which were set in worlds that barely started to know the new reality.
As a mystery however, I find the book slightly less engaging. The book opens with the locked room mystery revolving around how the scientist could've been turned into a zombie while he was preparing for his presentation in a private room, but the book doesn't really focus on that: that part is mostly ignored as we follow Ruri, who uses the excuse of being hired to investigate the locked room murder, to look into the research of the zombie-fied scientist, digging into a bigger conspiracy, which, due to numerous flashbacks to her past interspersed between the chapters, is obviously very much connected to herself. More than half of the book feels more like a private eye-type of story, where we see Ruri and her sorta assistant poking around, making people in Ultimate Medical nervous and occassionally some moves being made to get Ruri off the case. Some readers might find this more interesting to read as there's always a new event coming up, but I myself find it less interesting because at times, it just felt unfocused. As the book continues, we learn a lot more about Ruri's past which will eventually tie back to current affairs, but I didn't think this part really interesting. I believe the book was originally published with a YA horror-focused imprint, so I guess I shouldn't be expecting a hyper-puzzle-focused mystery out of this, and depending on your mood, the private eye mode of the book might be satisfying enough, but I personally felt it a bit lacking, with a few surprises which were telegraphed too obviously.
They don't completely forget about the locked room mystery of course, so we return to it at the end of the book, and it's an okay mystery, that makes good use of the unique world of the book. It's not a super complex trick however, and personally, I would also have liked a short story version of this that only introduced the world, the locked room murder and without the bigger conspiracy Ruri is after, because then I think it would have stood out a bit more, but as it is now, it's an okay locked room murder, which however is set aside for a very, very long time, so the impact is lessened.
By the way, I mainly know Kobayashi via his Märchen Murder series, which has some rather unique conversations which I always thought were because the stories were based on books like Alice in Wonderland, with characters speaking in roundabout manners and jokes based on misunderstandings and wordplay, but you also see that, though to a lesser extent, here too.
Overall, I did have fun with the book, but its main selling point is definitely the world that is portrayed within its pages. Don't expect too much of the locked room mystery mentioned in the blurb, and you'll have an entertaining time, especially if you also like the Märchen Murder series as it as a similar vibe. It's not very long either, so works great as a 'light-weight' book to be read between other books.