Don't think, 'I can't write that! People will be shocked or repulsed or disapproving. Or they might laugh.' You need a reaction, otherwise there's nothing to elicit a gasp or a giggle from your readers.
You can always delete things at the next edit. So let them go in at first. Then look coldly at what you've written the next time you revise it and you will know if it's good or not. It might mean that you can't send it to the publication you had intended it for. You have perhaps added things that render it unsuitable. But there is always somewhere else where it will find a home.
So, if you hesitate, write it anyway! You'll find out in time if it was worth it. And sometimes it is! Write as though no one is going to read it. And if you find yourself gasping/giggling, then you'll be sure you've got something good.