5/10, probably wouldn't read it if it wasn't written by Eve. The art awsome btw, all I'll be talking is going to be about the story part.
First of all I love Eve's work, also the newer manga, Inochi no Tabekata is one of my favorites. But this one is clearly a stepping stone on writing.
BIG SPOILERS!!!
The pacing of the story was too fast, the protagonist clearly had a special thing going on with them but it was only being told that he was special, not shown. Even in the end where they did properly explain it they just dropped as a lore bomb with text. Oh and the villains, their motivations were too absurd or too lightweight if you'll ask me.
The first villain shown, Yuu was just hunting down our protagonist for some reason(which is a good mystery tbh). But his abilities were too vague that rather than trying to understand his intentions we and the characters were trying to understand what he was doing in the first place.
And for some reason his shadow was his sister and they were merged and signed a contract which is kinda suspicious if u ll ask me <.<
Jokes aside the motivations were kinda linked by hierarchy. Yuu is motivated by it's shadow, shadow was motivated by this big villain which just showed up for a couple of chapters before saying "it's to help you" like that is true.
Now on the good parts:
The universe and the idea is real great. You could explain it simply as, pokemon with more direct connection with the host. But of course that is deeper than that.
I personally like Baku the most, his solo form is real cool (the one in the animated music). I love the goopiness of the shadows as well, it really feels like shadows given forms. Host-zingai relationships are really good too.
In the end I would only recommend this if you are a big fan of Inochi no Tabekata like me and crave for some more content from Eve.
But I strongly suggest reading Inochi no Tabekata, if you liked this one you are guaranteed to like Inochi no Tabekata as well.