George R.R. Martin opened the door for brutality in escapist fiction (though plenty of people had broken through it before) and this is a book which could not be told any other way. The Grey Bastards is full of all of the above in a thoroughly unsanitized way that will likely put anyone who cannot handle Deadwood meets Game of Thrones. These are some repulsive characters at times but the irony is it also discusses a lot of ideas which you normally don't see in fantasy like toxic masculinity and identity politics.
Okay, yes, I can already see that I've lost some of my audience but this is an incredibly intelligent book in the disguise of an incredibly coarse book. Actually, I think it's both which is part of its charm. I read it last year in its self-published run and said it was my favorite book of 2017, just above KINGS OF THE WYLD. I maintain that distinction while also acknowledging its hard to read at times.
The premise of the book is both simple as well as complex. The titular Grey Bastards are a group of half-orcs which live on the border between orc and human lands. They're employed, more like tolerated, by the kingdom of Hispartha as a defense force against their orcish ancestors. Jackal, a young upstart, is full of pride in this job while his pack's leader in the Claymaster is more ambivalent. They have a single female member, Fetch, who Jackal seems to have made his girlfriend without bothering to see if she was interested. Jackal tries to do a number of heroic things and ends up consistently finding himself worse off for doing so. He also discovers a lot of what he believed was the heroic history of his group was made up.
Jackal is, in simple terms, kind of an idiot. He's been raised on a steady diet of machismo, sex, and violence to the point that he is nothing but walking swagger. Virtually every single reaction he has is trying to satisfy one of these needs and it constantly fails him once he's in any situation which doesn't involve killing people or paying for sex (and sometimes then). The critique of the kind of character which is normally the protagonist in these kind of books (and is) works well but requires you to follow his perspective for a lot longer than many readers would be willing to.
There's a few maddening moments, also, where Jackal misses people have deeper feelings for him than he believes. He basically thinks Fetch will be his mate after he becomes leader because he likes her and he has a friends with benefits relationship with a local prostitute. One of these characters actually cares for him, though, and the other is much more conflicted yet his opinions of which is worthy of his affections dies hard.
Jackal isn't someone who is entirely to blame for his ignorance, though, because the culture he was raised in was designed to give the half-orcs undeserved pride in their lives. Well, undeserved is perhaps an unfortunate choice of word. They're a race of survivors, born from war crimes and slavery, which has nothing but scorn from both sides of their parentage. As such, their elders have raised them with pride despite the fact they are considered cannon fodder at best (and something worse at worst) by the human kingdoms. Which is better, the comforting lie of being a proud warrior race or acknowledging the cold hard truth that no one wants you? The book is pretty savage in its deconstruction of "honor" all round.
Much like Joe Abercrombie's THE FIRST LAW TRILOGY or the Sandor and Sansa sections of A SONG OF ICE AND FIRE, this is a book which takes a brutally cynical look at the idea of the worth of being a honorable warrior. Like some books I've read, war is often described as the young being sacrificed to a bloody god for the benefit of the wealthy with the young eager to jump into the god's maw. Jackal wants nothing more than to be a great warrior by his people's laws and traditions but they are full of traps all the way down. You start to feel sorry for the guy about halfway through. At the end, I was thinking it's better to appear to be an honorable warrior than ever actually be one--and that's a familiar enough lesson for grimdark fans.
There's a lot going on in this book and I've really just touched on the specifics. But it is a book filled with coarseness. The word fuck appears 230 times, shit appears 69 times, and 19 times for the word quim which we have the Avengers' Loki to thank for bringing back into prominence. That's not including another 20 different variations on a woman's vagina. The Grey Bastards culture is casually sexist and outright misogynist with some as they are a cult created around giving themselves pride in being manly men who do the manliest thing imaginable of murdering their fathers' species.
If you're not put off by that then I suspect you'll very much like this book. The world building is strong, the action is intense, the plot is well written, the revelations surprising, and the characters deep. It also has a theme which is analyzing where the "Proud Warrior Race" stereotype of so many cultures began. Plus, there's enormous pigs they ride and that's awesome.