Sekien no Inganock is essentially the bastard child of Perdido Street Station and Revolutionary Girl Utena. Think slaker moths crossed with the dueling forest, with added steampunk ambiance, and you're halfway there. It's not quite as good as that description makes it sound, but in the strange realm of visual novels it stands out as one of the most distinctive and least known.
The second of the cult What a Beautiful series, it is a dark fairy tale set in the sealed city of Inganock. Despite being home to fantastic beasts and even magic, the city is wracked by corruption, disease and constant mutation that has been slowly warping everyone in the city into animals since the day when the sky was covered by fog. In this sick city, you are a doctor, Gii, who wanders the street helping the sick and the dying. But when he meets a mysterious girl and runs up against an incomprehensible horror, he becomes embroiled in a series of trials in which the fate of the city itself is at stake.
Sekien no Inganock is different in a lot of ways. Its sketchy, fantastical art style is a world apart from Key's sad girls in snow. The story is both episodic and deliberately repetitive, with frequently repeated chunks of text and fight scenes that end the same way each time. A more cynical minded person might call this lazy, but when approached with the right mindset the repeated text adds greatly to the atmosphere and intensifies the ritual nature of the story, very similarly to the way stock footage is employed in Revolutionary Girl Utena.
Others might be irritated that very little is explained, on the surface. The end wraps up a number of questions, but a number are either given a vague answer or are left to the reader to interpret. Although this initially appears frustrating, there are certainly enough hints given to puzzle out almost everything of importance that remains unexplained; a series of short stories published after the game was released help tie up loose ends.
Sekien no Inganock is not for everybody, but those willing to give it a chance will find perhaps one of the most enchanting visual novels ever written. It's scrappy and imperfect, but whatever flaws it has are more than compensated by its strengths.