Okay, I have a lot of experience with Skyrim and the lewd mods made for it, so I think this is going to be a long one. Buckle up.
First, I'll reiterate what many others have said. Skyrim is a game made by a big game studio and then modded by a huge modding community. If porn games were made by big game studios and given tens of thousands of hours of work, they would probably be pretty impressive.
Second, while I did thoroughly enjoy lewd Skyrim before coming to this community, it is not without it's flaws. I realize vanilla Skyrim has tons of fans and even I played the shit out of it before adding any virtual nipples to it, but it's still a flawed game. It's certainly not the best RPG I've ever played. The combat is simple and often janky, the basic magic system is uninspired, quests can be really hit and miss, etc. Beyond that, there are lots of bugs with gameplay and quests. I could not force myself to play Skyrim without console commands after a while. I'm not even talking about cheating for laziness sake (which I sometimes did). I'm talking about this NPC is stuck and I have to teleport them, shit like that.
Now, Skyrim with mods (sfw ones) starts becoming a better game. You can fix lots of the underlying issues with vanilla and just add more stuff. You can greatly improve the visuals and the variety of items, spells, and quests, etc. I never got much into the combat overhauls, but even those types of things exist. After I had played the game to completion (as close as it gets) several times and tried most approaches to most of the quests, I started "enhancing" the experience. Other than making all the ladies sexy and the armors essentially reduced to lingerie, there was, of course, the fucking.
There are relatively few (as of my last foray into the scene) long narrative experiences of lewd content. The adult narrative mods for Skyrim fall into the same spectrum as the games and VNs on here. Some are hot garbage and some are pretty decent. So outside of a few exceptions, it is often put on the player to make their own fun. My personal favorites among the mods of this nature were sex as punishment (for crime and for combat) and forced bondage. It's sort of the corruption genre, but without a real story (so exactly like the corruption genre, jk).
The only reason these sort of make your own fun mods even worked (on an experience level, not a functional lever) are that they were built on the back of a fairly serviceable core game. The individual modders didn't have to do most of the "heavy lifting" when it came to the game itself. Sure, there are some very in-depth mods that took countless hours to make. They still didn't have to also make the whole game. They were adding a room to a mansion instead of building the whole mansion as it were. There's an intricate network of interconnected mods. You need a sex mod for the prostitution mod to even function. Obviously, the nude models and adult armors/clothes are generally stand alone and are purely visual.
At the same time, if someone delivered me a sort of sandboxy adult game and I was supposed to make my own fun, I'd be less interested than one that had a decent story. I did try my hand (wink) at adult mods in the Sims. While they have their own charms, they do suffer from being fairly shallow. You can now make people fuck, enjoy. To me, the fun was still from making my own stories. The father bangs his daughter's friends at her birthday party. The woman goes streaking in the park and fucks some guy in the bathroom. I can play out little scenarios, but at the end of the day, I have to provide most of the context. If all I'm interested in is people fucking, there's regular porn.
So is modded Skyrim the best adult game? I would say no. Is Skyrim one of the best game platforms for adult mods? I would say yes. I can't think of another single game that has such a huge catalog of adult content. Can you make a great adult gaming experience with the right selection of mods in Skyrim? Absolutely. I am just hesitant to call it the "best." I think it is more fair to judge individual mods against individual games/VNs and then it's obviously a case by case basis.
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