"Funbag fantasy" is a type of adult entertainment content that involves fantasies and scenarios related to female breasts, specifically focusing on the idea that they are magical, enchanted, or possess special powers. The term "funbags" is a slang for female breasts and often implies a lighthearted or playful tone associated with them.
In a porn video tag context, this means that the content may include scenes where characters touch, kiss, or engage in sexual activities involving female breasts with an element of fantasy or magic attached to it, typically for the purpose of turning on the viewer and providing entertainment for those who enjoy this particular aspect of adult content.