Real coherence problem at the end. I almost want to give it only one star just for that.

Short version: I'm not sure who the duck is. ( )

Some quick thoughts:

Originality
Not having read Hal Clement's work, I can't say how original Tadano's work is as an adaptation. Nonetheless, I can't recall when I've encountered these kinds of aliens, which provide food for thought.

I'm getting tired of the "gotta save your loved ones" trope. Is that a shonen requirement?

Artwork
I love Tadano's depiction of the horrible states into which people transmogrify. They leave you with a very organic, syrupy, moist feeling on your hands.

Characterization
Hikaru's supporting characters are fairly stock (the tough friend, the caring step-parents) yet believable. Even the alien personalities are not terribly complex once you get to know them. Interestingly, her childhood friend, Masaya, is more complex and his character is morally ambiguous.

Story
The narrative is well-paced and succinct--I had to go back to reread what a "subspecies" was.

Personal Notes
It's a strange mix of teenager concerns and a cursory exploration of the nature of the universe. The story, its originality and the artwork made it work for me.

I ordered Hal Clement's [b:Needle|939758|Needle (Needle, #1)|Hal Clement|https://d.gr-assets.com/books/1259445872s/939758.jpg|924733] through inter-library loan.
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