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But I think this story is about slavery. This is all about Niro fighting against discrimination. He might be even forbidding slavery in the futur if he become king.
It's very important.
If you want a strong individual who's getting stronger for his mom or his friends without being interested in dynamics in the country there are a lot of others stories.
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It’s not like slavery is all of the story. But no matter how strong niro gets there are always gonna be people who discriminate him for his background. I think that would be normal in this kinda situation but despite that niro has grown and made friends so I think the author is doing a really good job juggling the character growth and the slavery bias. Just my opinion, but I totally think the slavery bias is necessary to strengthen his character.
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The beginning after the end (a second chance for a bored king, building strengh while growing up in his second life)
A Returner's Magic Should Be Special (strong mage but his real stregh is his mind, but it's really good)
Solo Leveling (if you don't know this one, he's really apreciated by a lot of people)
The Scholar's Reincarnation
Tomb Raider King
Out (Makoto Mizuta) (This one is... a little violent. But you might like it if you want fight fight fight fight fight)
Badboys (didn't read this one, but recommended in the comments of Solo Levelinf (or another) so it miht be good)
My Status As An Assassin Obviously Exceeds The Brave's (don't really know where it goes, but it's a good kill time I think)
I come back if Iink of others lol
Can we all stop on exploiting because someone else is slave? Can we all move on and make this Niro as strong individual for everyone? Or this author don't have anything but cultivating on the story with slavery??? Tsk tsk