I see I am late to this party, but EXO by Fonda Lee is a YA SF novel in which humanity is peacefully subjugated by an advanced alien race. Earth becomes an outpost planet of the alien empire and humans kinda become second class citizens. Kinda like if mostly peaceful space conquistadors showed up and set up shop.
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It might be worth a read if you are enticed by the premise, but it is more Young Adult than sci-fi, as the plot mainly deals with the protagonist, the son of a high ranking human official, becoming entangled with the resistance movement. It was an enjoyable read, but nothing to write home about. I read it because a friend who doesn't read much (sci-fi or anything) really liked it.