Three reasons Humanity Has Declined deserves your attention:
Wit. In a medium where appreciation of irony often seems at a premium, Humanity Has Declined stands head and shoulders above with its bracingly open satire. In the course of just twelve episodes, the show sets its sardonic sights on consumerism, manga culture, corporate hierarchy, government, religion, and more. This is not an anime that pulls its punches.
Whimsy. You might think using three-inch-tall, permanently smiling fantasy creatures as a primary plot driver is strange enough, but that’s by no means the limit of Romeo Tanaka’s imagination. Try skinned chickens falling like manna from the heavens as the Ave Maria echoes in the background. Try a sentimental homecoming between two anthropomorphized space probes. Try the rise and fall of entire fairy civilizations in twenty minutes. I could go on.
Stellar voice acting. Humanity Has Declined wouldn’t be half the show it is without Mai Nakahara, who knows exactly how to sell the protagonist’s deadpan humor. The rest of the cast is nothing to scoff at, either. Miyuki Sawashiro turns in an almost predictably excellent performance as Y, while the various fairy voices serve as a perfect mix of saccharine innocence and morbid darkness.
9/10. This is show of the year material.