Originally Posted by AIbenjamink

If you are selling nudity, or anything else adult related, you will want to be sure your selected script integrates with a billing provider who allows payment processing for adult goods.

Simple member management/password protection functionality is provided by most 3rd party adult billing providers, allowing you to protect a directory and any content which it contains. If you are starting with a simple member setup, you may want to do a little bit of research on htaccess, and how its implementation can be used to protect your site.