I think, such stories work at best for original characters without a real backstory, but not so well as parody.
I'm not sure I understand. If the characters don't have a backstory, doesn't that mean we don't know their relationship, and therefore, the couple might not necessarily be a couple but friends, and Inoda joins in and becomes the girlfriend's boyfriend/sex friend/ Master behind our backs?
I apologize if I misunderstood. In any case, I do struggle with the NTR genre, especially when the antagonist is portrayed as a hero who saves the girl while actually being a scoundrel using substances like aphrodisiacs to seduce the girlfriend and divert her from her boyfriend.
If Inoda had done things properly, as in NTR games like "My Neighbor's Wife," for example, I wouldn't have been disappointed, but having your girlfriend stolen by a loser who later becomes a SEX GOD with our help is really lamentable, especially since the MC is completely oblivious to the situation.
I do like the NTR genre in works like "Fleeting Iris" (because there are multiple possible choices), "My Neighbor's Wife 1 and 2" (because we are the ones stealing the wife, and we do it properly), and finally, "NTR Dojo" (because we are the one stealing girlfriends and wives, even though in this case, the guy is a real pervert, but well, since we choose and initiate it, it works).
