Issue with ntr as a whole is it's a very "all in" kink. Even entire anime or manga series have plummeted in popularity or been outright cancelled because, for whatever reason, the love interest, that's loved mc for who knows how long, decides to bang a soccer player that's objectively worse than the mc in every possible way, but for some mind numbingly stupid reason like "mc cares too much for me" or "well he can mildly inconvenience the mc if I don't" the love interest does so. This results in the audience being ""divisive"" at best. The only way to really sell it to the correct audience is instead to isolate it and make it on bold on the tin a title involving "ntr" "cheating" or have it blatantly in the description so it's only the buyers fault not a trap.
Some have success however with the mc being or becoming a bull, like very early in the series the gf does that, and the mc finds a big booty bad bish or a harem while the original gf is crying in a corner. Coc2 is perfectly setup for the pc to be a straight hentai level bull, you can have a friggin magnum dong that a witch can buff so each individual drop of sperm is instant pregnancy, and you have a Olympic pool sized reserve, with ever expanding balls that are also enchanted to only ever be half full. It's ludicrous that there's so much cuck content when your character in the corner can have a 12 pack and pack a breeding tree in their pants.
I don't think there's inherently a problem with cuck content being in the game for some characters, but there really needs to be equal opportunity to cuck in return, they just seem afraid or reluctant to do so because they think their characters matter and nobody else's does or whatever other reason. Takahiro can bang whoever he wants, including your side love interests, but you can't bang azami or yuzu, cait can get lusamine gangbanged and you can have the privilege of watching etc. The primary sexual incentive for swinging or being cucked is competition, biological drive to fight for who gets to be daddy yadda yadda, not sitting in the corner or being a living bed. They really need more of your character sneaking behind other characters love interests with a ugly grin if they keep wanting to add more ntr or cucking, after all, if it's just a smut game and people can bang whoever they want, then their partners ass is free real estate, also.
I pretty much agree with most of this. And I have an example for how it can be done better and worse than Coc2.
I've been playing through
How to build a Magnificent Kingdom which is basically an Auto Battler inspired by Fire Emblem and hentai. Now the premise of the game is for an unknown reason the king went crazy and started killing a bunch of people in his kingdom. This lead to the kingdom falling a part and the Princess basically has to pick up the pieces. As only Her, a maid, the commander, the hero and her side-kick that defeated the king and of course MC-Kun are left in the kingdom. So to revive the kingdom she basically says lets open a brothel. Where, her, the maid, and the female hero will sell their bodies to get people coming back to the kingdom. You recruit more girls as the story progresses and you can romance all of the females recruited or send them to work in the brothel.
How to do NTR right
The thing that HBMK does well is you can completely ignore the brothel and just marry all the females you recruit. Even without using the brothel everything is still unlockable/upgradeable, and the only thing you miss out on is watching the love-interest banging other dudes. The brothel is completely unimportant. The game also allows you to choose all the girls romantic history at the beginning. It can be set to virgin, they have some past experience, or turbo-slut. For the most part you can avoid being ntr'd/cucked. With the exception of one character Lynne.
Additional context
Now in HBMK the first run always results in a bad-end. Its unavoidable. I thought if I ignored the brothel I'd avoid it. But, the bad-end happens regardless. So, the bad-guy basically outsmarts you and all the female character basically start to embrace their terrible traits. Now at first this didn't bother because many of their negative aspects were being explored before the game did a 180. To give an example Anri is completely obsessed with getting stronger, so she can get revenge. You're aware of this and everyone around her is saying don't use the evil sword, you're not gonna be happy. Casco in her support conversations with Anri is the most vocal about this, but when you guys are trying to escape from the literal Devil, she decides to use the sword. Not for revenge but to save you and everyone else. Now she's a serial killer. While its tragic, its develops her character, and it shows how much you and the rest of her friends mean to her. As when you finally find her again she completely regrets using the sword and is waiting for Casco to chastise her, but Casco doesn't as she acknowledges Anri did what she did to protect everyone. And all of the other heroines made similar choices when escaping. Its a twist I'm mixed about, as it furthers the entire casts character arc, but I personally don't like that its required that you get the bad end. (Haven't completed my first run yet, but from my understanding the second run of the game allows you to get the true good end.) It's basically like how Chrono dies no matter what during the first encounter with Lavos, but you can making things better later.
How to do NTR wrong
The problem I have with HMBK is Lynne who is a Nie. The Nie basically believes its their clans duty to give themselves to the Devil (not in a sexual way, but human sacrfice) to save humanity. Basically Lynne's arc is learning to think for herself. But what this results in her doing is hoeing herself, as she doesn't want to think. (Lynne is also not a bimbo like Cait. She's completely inexperienced both in sex and knowledge of the world. Essentially she's naive.) Now this didn't make sense to me, as if you make Lynne part of your harem and marry her, all of her scenes are all about how she's completely obsessed with you. Everyone in the kingdom comments about this, and it get to the point where she's like "I really don't want to sacrifice myslef to the Devil, because I love MC-Kun so much" The game even doubles down on how much she loves you, because when the Devil is about to kill you she steps in and saves you. Which the Devil even comments on basically saying "what're you doing. You're supposed to be my food." Now after that she start sleeping around and asking for extra shifts at the brothel (the one that doesn't exist in my play-through)
Not Kink shaming
Now I have nothing against people who are into ntr, but like undyingrevenant was basically saying in games that are trying to appeal to everyone its good to give the opition to opt-out of certain scenes. Like HMBK has little bit of everything, and all kinks can be opt-out of. Don't like loli's don't romance them. Don't like pegging, don't click the choice to get pegged by a loli's dildo. But the scenes with Lynne are out of character. It doesn't make sense that she would just suddenly start banging random dudes, especially if you've never opened the brothel. For the people who like Lynne the most this would be a massive kick in the nuts, made worse by their being no signs pointing to it. (As her arc had nothing to do with her sexuality.) And even knowing that this won't happen in the true ending it still sucks.
And this is pretty much the problem with all of CoC2 ntr scenes. Atugia who was a kiss-less virgin is suddenly blowing Arona (and while I've never seen it apparently there's a scene where she bangs brint) The pink elf who is obsessed with champ suddenly letting Brint breed her because Ethryn needs an heir. All of the ntr scenes feel completely out of left field. Its one thing if they were purely lose scenes or like suggested exclusive content for Cait as she's the resident turbo-slut.
But this has been your daily overly long post about how CoC2 sucks and how other porn games are better. (Some of the time)
Edit: In short either go all in or always allow the player to opt-out scenes they might not like.
