"Gay shower" in the context of a porn video tag refers to a scene or video where two or more men are engaged in intimate, sexual activities while showering or in a wet, soapy environment. This type of content is categorized under "gay" because it features male-male interactions and sexual acts.
A gay shower scene often includes elements such as soap, water, and slippery surfaces which add sensuality and eroticism to the interaction between the men involved. These scenes are typically aimed at an adult audience who enjoy this specific subgenre of gay pornography.