The porn video tag "free-gay" likely refers to a video that is both available for free and features gay content. In this context, "free" indicates that there is no cost to view or download the video, making it accessible to anyone who wishes to watch it. "Gay" denotes that the content of the video involves sexual activities between men. This type of video would be appealing to those interested in watching gay porn and looking for content that they can enjoy without any financial barriers.