This porn video tag, "zombie-retreat-sex," refers to a specific type of adult content that involves three main elements: zombies, retreat, and sexual activity. In this scenario, the zombies are likely fictional or supernatural creatures who are either undead or infected with a virus that causes them to crave human flesh. The term "retreat" suggests that the characters in the video are in a location away from society where they engage in sexual activity. This could be a safe haven or hideout for survivors, and the combination of fear, danger, and desire leads to explicit sexual encounters between individuals. Overall, this tag indicates a pornographic scene with a zombie or apocalyptic theme taking place in a retreat setting.