Quick Thoughts:
Outside of some nostalgia from the flash-style animation, I didn't get much out of this series. With its 5-7 min long episodes, cutesy art-style, and episodic format, It seems like the target audience was much younger than me unfortunately.
Story:
This series was mostly episodic. There's suppose a story-line involving someone pursuing the main character, Xiaohei, for a pearl he possesses, but it was too fragmented for me to follow. It ended up being a slice-of-life comedy type series following Xiaohei as he interacts with and learns more about the human world. A comparison that comes to mind would be Natsume Yuujinchou.
Art:
The art-style was simplistic, but nice to look at. Animation was pretty smooth overall, including the several fight scenes throughout the series.
Sound:
Voice-acting was serviceable I guess, a lot of meowing and other animal sounds. Music was fine during the fighting scenes, didn't notice it much outside of that.
Characters:
I didn't find any of the characters to be notable; they were all pretty basic. Not much development either, though that's to be expected considering how short the show is.
Enjoyment:
As mentioned before, I got some nostalgic enjoyment out of the animation; it reminded of the Newgrounds era of the internet. That ran thin after a few episodes though. Even with the series being less than 3 hours in runtime, it felt like slog to get through the rest of it.