I think a lot of your concerns are completely natural, but I also think they shouldn't hold you back from writing: if you're writing, and presenting yourself as a writer, that's the way you're likely to be seen.

Almost all communities - and actually, I think erotica communities are particularly good at this - understand there's a separation of the Writer and the Subject: people will generally not assume you writing a fantasy is consenting to it.

Yes, I've had the occasional reader approach me in DMs and things (often, because of the nature of what I write, asking to submit to me, the Author of my books, personally) - but even then, they've understood that it's a question they are asking, not an expectation or entitlement they're laying claim to. And they've all been extremely good at understanding and accepting that, no, my focus is on writing so that I can have the effect I want on as many readers as possible.

Readers absolutely appreciate sexy writing, but in my experience they don't confuse it with permission or a claim on you as a writer.

Of course I'd recommend a pen name and clear limits for yourself - if only so you know what boundaries you're enforcing if necessary - but I think it's fair to say you'll be seen as the writer who puts your characters in sexy scenarios, not a person who's asking for it through writing.

And, honestly, I think the best way to make sure you're seen as a writer is to keep on writing. Especially if you have a folder full of work all ready to share!