The porn video tag "gay anime (gay)" refers to a specific genre of adult content. In this case, the term "gay" is used to specify that the anime content features homosexual relationships between males. So, this tag implies a video containing animated characters engaging in sexual activities with each other, specifically involving male-on-male interactions. The use of the word "gay" in parentheses is likely to emphasize or clarify the nature of the content, as it might be a part of a broader category that includes various types of adult anime content. This tag targets an audience who appreciates and seeks out this particular theme within the realm of pornographic animation.