Got one idea that goes like this:
What I had in mind was a fantasy setting where a tribe of some kind of anthros invades an area where my character and yours live in a slightly secluded house. The monsters could overpower my character and capture yours, perhaps raping her right there in front of him. However, they have larger cocks than most humans and give off pheromones which get women all hot and bothered so your character can't help but start to enjoy it, even having orgasms and losing herself. Later, the tribe might take them as prisoners, using her for sexual needs. This opens the door to all kinds of humiliating situations, for example, once your character comes back to her senses from her sheer ecstasy at being fucked by and sucking such manly, well-hung monsters, there is the air between the two of them who are very much in love. She has to deal with the fact that she was forcefully taken by other men but seemed to love it even as she was fucked in front of her husband. My character obviously dealing with the humiliation of watching his wife moan and love the cocks of other men. Then, since they are allowed to live together in their imprisonment, there could be several times when my character and yours try to re-capture their romance, since they are still very much in love, but when they try to have sex, she has been stretched by the imposing cocks of the monsters such that he really can't give her very much pleasure. Also there's the humiliation he suffers from watching his wife orgasm at the hands of the crude monsters on a nightly basis. It doesn't help that she starts fighting less and less when the soldiers of the monster tribe come into their very house to use her as they are entitled to.
I am totally open to other ideas, any involving cuckolding, but this is just an example of some of the elements I'd like to incorporate. I'd love a traditional cuckold RP where the wife is basically feeling unsatisfied and the couple agrees that she can sleep around so she starts bringing well-hung guys home and the husband either has to sit in the living room or something while they fuck in his bed, or has to watch and "clean up"
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