So, this was interesting. Wren is a mute, albino omega in a future that includes some pretty devastating environmental issues, including a sinking city.
When she ends up in the warrens, which is basically a homeless camp of sorts, she somehow ends up adopting the care of two boys (how this happens is not explained. There is a lot in this - way too short - book that is not explained). When the boys go missing, she just waltzes into the lions den to retrieve them and ends up on the radar of the underground mafia head and his two alpha associates.
That is where all the sex comes in. Of course, nothing is free and she needs expensive medical attention for her youngest charge, so with nothing of value to trade, sex it is. This arrangement includes pretty much anyone the big Alpha includes which starts with the Alpha and his first and second alphas. BTW, the older kid has just disappeared after she brings him home.
Everything is made a bit more difficult because she is mute and they are not especially intuitive. Calling this a reverse harem is really just new code for gang bang, kind of. These guys are overly aggressive sexual guys with no impulse control (or need for such control, there is nobody to insist they show any) and don't seem to have any issues with having sex with each other. Either as part of the playtime with Wren or as dominance positioning/punishment - although that is just mentioned, sadly. One more place this book was really too short and skipped too much.
Be warned. Here is the thing. This borders dubcon which I don't have any issue with (in my fictional erotica), however, I did struggle with the writing to determine just how much abuse vs unwilling pleasure Wren was actually enduring. She was portrayed all over the place with her reactions and I just never got a hold of where the line was for her. And... there is a lot of fluids in this book, I mean so much sexual bodily fluid...hers and theirs and combined some of the descriptions just kinda grossed me out at times. I didn't find her laying in soaked bedding for extended periods as erotic. It just doesn't do it for me.
And the worst thing to beware of is this is a VERY SUDDEN CLIFFHANGER. It ends at like 85% because it contains an excerpt from earlier books. Honestly, I would read these books but I won't ever read them again until they are all published and the series are finalized.