There's an interesting set of ethical questions surrounding the ways that people with socially unaccepted preferences/fetishes use technology to satisfy forbidden urges. If we accept that individuals aren't able to (and generally shouldn't have to) control what they find sexually attractive, then it seems admirable to be able to use tech in ways that don't harm any actual people. If LLM erotic roleplay begins to replace the highly exploitative realworld porn industry (which of course uses real humans, many of them psychologically, socially or financially vulnerable), that seems like progress.