Army, you're not wrong, but I personally find the word distasteful due to its meme status. Here's a long-winded rant explaining why!
Now this is just my impression and understanding of things I am neither a psychologist nor professional pornomancer, so my understanding might be flawed or incorrect. If that's so, sorry, but I'm the one writing this post and anyone who disagrees is free to make a rebuttal.
Cuckold is fine as a word. The word has been around for hundreds of years. It used to be only a negative term and it implied the male was unaware. It's something you called the guy behind his back while laughing and drinking with your buddies or to his face if you wanted the poor bastard to do something stupid.
At some point, fetishists--being notorious as assholes who take things to extremes but usually have the decency to keep their shit to themselves--started using it for a male that was aware of and encouraged his partner's infidelity.
Then, the Internet got involved, and as we all know the Internet ruins fucking everything. Fetishists on the internet--being notorious as assholes who take things to extremes and refuse to shut the fuck up about it--started popping up and cramming it into everything the same way they did with scat, futa, an inexplicable love for blue hedgehogs with rapid acceleration abilities, and any number of other kinks.
I don't know much about the scene because it's not my bag, but I presume there are companies specializing in cuckolding porn designed to be watched by couples to play out their fantasies in a safe environment like any other fetish. But the vast majority of internet porn is gonzo porn and the the vast majority of that vast majority is designed for male consumption.
And so the content of cuckold porn you're likely to see on the web goes way off the deep end and where one might have expected to see some voyeur stuff or phone play accompanied by roleplay and acting of questionable skill, they are instead treated to some black guy railing a porn star while a white dude is humiliated and cries while jacking off. The average dude surfing the web who sees something like that then says something to the effect of, 'What the fuck?! Nope, nope, NOPE!' and hopes to make the correct turn at Albuquerque next time, possibly throwing in an added bit about how gay the whole thing seemed.
So, now we have everything we need to create the best insult since faggot and we can proudly say the Internet did exactly fucking that. And thus cuck was born.
Disagree with someone?
Don't have an argument?
Just want to be a dick?
Pissed off about the direction they're taking your favorite DC superhero TV show in?
Call someone a cuck and you will both instantly win and feel better for yourself!
You might be a loser, but at least you're not eating some black guy's cum out of your girl's cooter like that guy.
Who's doing that!
Because you said so!
By calling him a cuck!
Then /pol/ found out about the insult and took it to such extremes that some people claim it is an insult of alt-right origin. Top fucking kek. So now not only is it a fucking meme, but it's a politically charged meme.
At this point, seeing cuck or cuckold in a discussion more or less gives off the same warning sign as bringing up Hitler or Nazis: This conversation has turned completely to shit.
People have always hated NTR themes, but go back five years and look at the insults and compare them to today's. The easiest way to shut down any discussion of NTR or cheating is to just come in and start screaming cuck. And that's what people do now.
Trying to use a different meaning, even if it's the original or correct one, of a meme is at best passé and at worst retarded.
I'm not going to get into what I think are the differences between the Japanese and Western impressions of the word right now, but I definitely think there are differences and there are reasons for those differences.
You could come up with any number of other ways to translate the Marina title without using memes. A willingness on their part to do so means they either don't understand the story and genre enough to care or they are deliberately trying to appeal to a customer base that I definitely don't want showing up here. :/
/end rant
I don't mind things like the phrase NTRed. It's just taking a word and making it fit to English conventions. I do that with Japanese all the time and they do the same with foreign words as well. It's more for the convenience of making it fit the language's sentence structure and so people that won't understand the term will at least get how it's being used.
Finally, it's fine to talk about netorase themes and games as they are pretty interconnected. As was mentioned, a game can start off in one way and introduce other elements as it progresses. I don't think people mind too much so long as it doesn't turn into a twelve page discussion on the desire to produce an off-Broadway Marina-themed rock opera.
Sorry for any typos.