Counterpunch - Aleksandr Voinov
"The moment the slave resolves that he will no longer be a slave, his fetters fall. Freedom and slavery are mental states.”

Mahatma Gandhi

Yes, Gandhi certainly was right. And this book story is an example. Why?

Simple, meet Brooklyn, a slave... a boxer slave.

Imagine a society where slavery is again allowed. Depending on the crime, you can be a slave. No way back... one time a slave, you know it's how you end your days.

I think in this story what most made me stop and think is not the erotic scenes, or the amazing well constructed world. I never saw it as a romance (and I strong advice you to don't read it if it's what you are looking for). Yes, it's there, the lust, the attraction, the need Brook and Nathaniel feel to be together, to help each other...
I must be VERY honest and say I was VERY attracted to the BDSM theme of master and slave, but I didn't saw it like that.

Brook is a slave, true, but he isn't. In his mind there is a constant fight to accept it. He is a slave, fighting, boxing as he always love to do, but he is doing it for a simple fact... to punish himself.

Yes, there is no innocent wrongly condemed here. He is guilty, and he will always say it.... and THAT'S the point!. He is not submissive, and he will never will be, but he accepted his fate as his own punishmient.

so, that's why I'm think another quotation is also perfect to describe Brook

"There is a higher court than courts of justice and that is the court of conscience. It supercedes all other courts.
Mahatma Gandhi”

Last Remark
I think the theme here more deep than it can seems. So yes, it's an alternative reality, it's slavery the punishment to some crimes... but when you will read it something will be very clear. It's not very different from your own society.
Brook is paying for his crime... but he is a slave because he kill someone, or it's a consequence of who is dead?

Good question... indeed a good question... the crime, or against who it was committed, it's the real factor that will lead to such hard punishment?

5 stars, I can't give less.

Footnote: it's a standalone. Even if you read it's part of a serie each book is a standalone. I didn't read book 1 to 2, just this one.