Story: 9/10 Pretty damn good, the anthology type chapters are good and the over-arching plot had me hooked. Many characters turn up in other chapters too so it doesn’t just feel like a bunch of random, unrelated stories. Some chapters were basically filler with no impact on the overarching plot or our understanding of the main characters however. There are fun adventurous chapters as well as some pretty dark and emotional chapters (seriously it gets pretty dark). The mystery of the witch was intriguing. The subplots were brought together masterfully. I liked how Kuro and Sen's backstory was handled, with it being built up over thecourse of the whole manga and with scenes that recontextualise previous chapters.

Art: 10/10
It's a 4koma but the boxes are bigger than normal 4koma manga, so the art doesn’t feel restricted. Frequent wide panels and coloured pages. Great art of the landscapes. The art always fits the tone of the chapter, from fun and whimsical to dark and gritty.

Character: 8/10
Interesting characters abound. The Main characters are well written and I enjoy the dynamic between Kuro and Sen. There are many reoccurring side characters, none of whom are very deep but they don’t need to be and they are used well. Sanju and Nijuku feel like actual children, naïve and curious about everything. Characters, and our understanding of them, grow throughout the manga. The eponymous Kuro can be somewhat inscrutable at first but you will get to know her.

Overall: 10/10
Not much more to say, a great manga from start to finish. Would recommend if you can deal with 4koma and episodic storytelling, you will not be disappointed.

Good
• The art is so good I literally didn’t notice it was a 4koma manga until it I saw "4koma" in the tags
• There didn't feel like there were any dud anthological chapters, the manga is consistently high quality
• Great ending, I was worried that it would be disappointing with all the build-up, but it delivered in the end

Bad
• Some chapters can be confusing, sometimes it felt like the pages had been jumbled up

Extra Subjective
• Episodic chapters