I first thought that this manga would be a trashy, edgy, romantic tragedy. Well, I was right about it being edgy. Let's begin the review.
Kasane is a very strange and twisted manga. There are a lot of disturbing themes in this, mostly involving women. It's no Goblin Slayer, but since apparently no work of art is allowed to make anyone feel even mildly disturbed these days, I still must warn you in advance.
The story was a lot better than I expected. It's a bit slow in the first volume, leading you to believe that it's going to be a repetitive 'steal this girl's face
for a while, steal a different girl's face for a while, rinse and repeat' for all fourteen volumes of the manga. However, once you get into the second volume and onward, things start becoming a real rollercoaster ride.
There's also plenty of twists and turns. I'd be surprised if I found out that story was improvised, because it holds up pretty well. Well, not to say there aren't flaws at all. Of course, there's the tiny flaw that a lot of bystanders wouldn't realize something when Kasane would switch faces with a blonde woman, and from their perspectives, that person would show up with black hair. That alone would probably be enough for a hypercritical person to tear this manga apart (since it's unheard of for an actor to possibly dye their hair), but to me, it's a small bump on a very well-paved road.
The characters are all as deranged as one would expect. With this being a psychological thriller, we naturally get to see deep into the way that the various people in this manga think. The various plays that are performed also complement one character or another at any given point in the story. Warning, though, this is one of those types of stories where everyone is morally incorrect in some way. If you don't like that kind of stuff, a la Rising of the Shield Hero, then I recommend you shy away from this manga now.
However, I think the art is where the manga is sufficiently brought to life. It doesn't look too impressive at first glance. But when actually reading the manga itself, I was glued to it. Somehow, the mangaka is able to skillfully portray humankind's stereotypical form of beauty, and at the same time twist that beauty into some demonic expressions (not to say that the ugly people don't have some of those moments as well). The panel work is also really well done to invoke as much emotion as possible.
Overall, Kasane ended up being a very, very good read. Although it's no Urasawa Naoki manga, it's still a solid thriller. I kind of hope it might get a TV anime someday; it would be an EASY two-cour adaptation. But at the same time, maybe letting the anime community see this with how GS and Shield Hero have been doing might not be a good idea... Well, regardless as to if that ever happens, this manga will still be a moving performance!