The porn video tag "gay glory hole" is referring to a specific type of encounter between two or more men. In this scenario, one or more men are on one side of a partition (like a wall with holes in it), and the other person(s) are on the other side. They engage in sexual activities through these holes, often involving oral sex (specifically blowjobs). This activity is commonly associated with gay encounters as it involves intimate physical contact between men without direct eye contact or personal interaction beyond the sexual act itself.
Tag "gay" simply clarifies that this scenario involves men engaging in same-sex activities. It's not related to the glory hole aspect, but it helps specify the kind of encounter for viewers who are only interested in gay content.