What does pre-checked mean?

Pre-Checked

Often join pages will include an offer to join another gay porn site and these offers can be pre-checked, meaning they're already selected (or unchecked, meaning you need to select them).

If you don't review the join page carefully, you could miss a pre-checked offer which will commit you to the offer. These offers are often trial memberships with more expensive rebilling options, so check the sign-up page carefully.