There is a well that is first dug at birth. As we gain experience in the world around us, it is dug deeper. Those experiences fill the well and mix with each other to create our identity. Some people avoid experiencing things and have shallow wells as a result. In order to write content that connects with people, one must have a deep well from which to draw inspiration. One must do things and interact with other people as much as possible when they aren’t sitting in their chair hitting keys and forming words on a screen or mapping plots out on whiteboards.
Great erotica is no different. It’s not about knowing 200 different words for genitals. Nor is it about knowing every kama sutra position or all the ways to say wet.
As writers, we are often told to write what we know. You have stories in you that others can’t tell because we haven’t lived your life. You also experience sex differently than others do.
While you don’t need to have done everything you write about, you do need to experience things that bring about similar understanding. Maybe you haven’t been whipped, but you have enjoyed being spanked by a partner. You can reasonably understand that some people enjoy pain and thus get away with writing about something more intense than spanking if don’t get too detailed without interviewing people in the BDSM community who are really into it.
If you are a virgin who doesn’t masturbate, you’re going to get any sex wrong in your writing. You’re going to base it on some porno or something you saw on TV, what you read about online, and your own ideas of what it is actually like. It will read hollow on the page. If you don’t have much experience, you’ll base it on those things and what you’ve done with one partner who may be a terrible lover.
If you are asexual and can’t fathom how anyone could be so attracted to another person during dinner that they yearn to clear the table and jump the other person, then don’t write a scene like that. Write one from a perspective that you relate to and help other people understand what sex can be like from that perspective.
Be safe, but experience things.