*This review is spoiler free*
This manga is something that doesn't come along very often and I recommend to be careful when picking when you start reading it; once you start, you can't really stop. That is because Made in Abyss starts off as a subversion of its presentation, the art and the character designs doesn't reflect the themes the story explores.
Akihito Tsukushi's art is what hooked me in, for without his unique art style, Made in Abyss couldn't begin with this subversion. The art is a very well made blend that serves as a well fitting medium through which the story is told. The highlights for me are the backgrounds/sceneries and the qualities of the base character design slate that allow for the fantastic variety of character designs and the emotive movements and facial expressions. To go even further, what specifically makes this art special is the weight in the emotional and action climaxes of each chapter that the art creates. When something of note happens in Made in Abyss, it is conveyed through the art with lines and contrasts so perfect for each event depicted that its a little scary how good Tsukushi is at this.
The characters themselves are great, and the main group is naturally the highlight of the manga's cast. Without spoiling anything, Made in Abyss has this ability to make me genuinely feel and root for characters. I think this comes down to the great art; the emotions that the characters are able to express feel real and have the weight necessary to make readers empathize or simply understand them. When a character grieves, I can't really help but grieve alongside them in a weird sort of sympathy.
I've thoroughly enjoyed the 47 chapters that have been scanlated, and I can't help but check every other day for new updates. I thoroughly enjoyed and will enjoy this manga; it's so different to anything else I've read. I've personally never really enjoyed genres like sci-fi, fantasy and adventure but this manga... This manga has something special, and I wholeheartedly recommend it.