This isn't much of a spoiler but each heroine has a route to themselves, and then there is one final route which is basically the 'true route'
imo Altera's route and the true route are the best ones in the game.
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I've heard good things about it, apparently the story and worldbuilding are really good or something.
I played an hour or two of it but I didn't really get what people meant. Maybe I need to play more. I just know the combat is super shitty.