Read this book: https://www.amazon.com/Insatiable-Wives-Women-Stray-Love-ebook/dp/B0056A8A2Y
Bad title, but full of interesting case studies.
It's been a fetish for a VERY long time.
On a more modern note - in the 90s, Penthouse has always had those fan submitted "penthouse letters". Basically erotica written by readers. The #1 category typically fell within the realm of wife-cheating/sharing in one way or another.
Men have a lot of anxiety about their own worth when it comes to infidelity. It's really no wonder all that anxiety manifests itself sexually. Anxieties have a way of doing that...
People always like to quote that the most hardcore homophobes typically turns out to be gay. And i don't think that's the case. I do think that ..spending so much time and emotional energy on it, will eventually drag your sexuality a certain way. So that's why you see random, family values Republican preachers locked away in a motel with their barely-legal boy toys.
Also - am cuck. That Daily Beast article has been floating around a long time. It's shit. Most people with this fetish aren't "intellectuals". Most of them barely understand their own fetish well enough to even think about acting on it without tearing their relationshps, nevermind their own psyche's apart. Cuckoldry is literally the result of sexually manifested anxieties regarding jealousy and infidelity as that times to your worth and masculine identity. And successful non-monogamous relationship of any style, has to be able to handle jealousy in a positive manner. These two things are at odds when people try acting out this fetish. That's why you end up with cyclic bullshit like this:
https://www.salon.com/2013/09/13/i_dated_a_cuckold/
Nevermind the guys who can't handle the reality of what they think they want.
This is a better article on the subject: http://www.nerve.com/dispatches/ma/cuckold
This is a fairly decent text on the subject: https://www.amazon.com/Insatiable-Wives-Women-Stray-Love-ebook/dp/B0056A8A2Y
The fact this word has been appropriated by the alt-right and has become mainstream lingo mentioned on daily tv and the likes of everything from Rush Limbaugh to the Colbert Late Night Show, kinda sucks.
Better yet, how about you read a valid source that I would parrot then we both stand on a factual footing.
https://www.amazon.com/Insatiable-Wives-Women-Stray-Love-ebook/dp/B0056A8A2Y
You’re in luck, it’s on sale! It’s a quick read.