Another version of Cock Block. In this case, a man is preventing another man from having sex with a woman by threatning him with a firearm.
Man 1: You even think about doing her, and I will kill you.
Man 2: Ok, ok. No need to Glock Block me man.
-Later-
Woman: Sorry he Glock Blocked you.
Man 2: He seemed the type to be teeming with insecurity issues.