A kid drops into a world that makes no sense and decides to trust it anyway. Endride commits to that optimism even when the plot gets weird, even when the world-building contradicts itself, even when you're pretty sure nobody involved fully agreed on what was happening. The real hook isn't solving the mystery of Endra, it's watching Shun refuse to get cynical about any of it, and somehow make that work as a survival strategy in a place designed to break that kind of hope.

Shun Asanaga, an upbeat and ordinary fifteen-year-old middle schooler, comes across a mysterious crystal at the company run by his father, a scientist and businessman. The instant he touches it, he is pulled into Endra, an unknown world lying beneath Earth's surface, where the giant Adamas glows overhead and bands of seven colors float across the sky. Meanwhile, Prince Emirio has reached sixteen, the age at which he may inherit the throne, and finally takes up arms against King Deruzain, the ruler he deeply hates. The king proves far too strong, and the defeated prince is thrown into a cell. As Emirio grieves, the wall of his prison warps and Shun steps out of it. Raised in two different worlds, the pair now share a path through Endra, one hoping to find his way home and the other still set on revenge, in a fantasy adventure about their uncertain future.