There are subreddits with model-generated porn stories. All the horny people writing for each other are getting automated. In the example I saw some people had sex and then took their clothes off at the end. It's groundbreaking stuff.
That was literally what like 90% of AI Dungeon (GPT-3-based CYOA adventure simulator) players were using it for. Then OpenAI forced AI Dungeon to implement strict content filters, and within a month the community had already stood up a fully functional replacement fine-tuned on literotica with 10 times the features and a focus on privacy and zero content restrictions. The community replacement was partially bankrolled by the sale of AI-generated anime catgirl image NFTs.
That's barely scratching the surface of the AI-generated erotica scene, it's pretty wild.
Funnily enough, so long as you aren't trying for porn it does a much better job than AI Dungeon did of staying away from it. It lives up to its name — it's an excellent cowriter for all forms of fiction.