The porn video tag "black and white gay" refers to a genre of adult content that features homosexual interactions between men. In this case, the term "black and white" implies that the video is filmed in a monochrome or grayscale format, giving it an old-fashioned or vintage appearance. The term "gay" clarifies that the focus of the video is on male same-sex encounters, which can include various acts such as kissing, oral sex, and penetration. This tag is intended for adult viewers who enjoy this specific niche within the realm of pornography.