The setting and worldbuilding were definitely the highlight of this game. The game was continually giving you glimpses into a landscape that was just very cool and original, and the worldbuilding on top of it did a surprisingly good job of making it cohesive for how wacky it was.
The various endings did vary a lot in how closely they tied into the other worldbuilding, and some of them were a lot stronger than others as a result.
I also found the mechanics fun. The game was simple to play, which balanced out the wackiness of the setting and the pace of the story nicely, and the mechanic of collecting and using names of the dead again felt very original.
I think the main area for improvement could be some additional quality-of-life features in the UI — the compendium is useful, but it would be nice to have it accessible from the input screen once you unlock it. Similarly, the undo button that appeared on the first screen after summoning a ghost was useful, but it would have been nice if there were a “replay current chapter” or “replay from last summon” button beyond that screen, to make it easier to see the ways your choice affected the rest of the chapter.