Masking in the context of a porn video refers to a scene or act where one or more participants are wearing a mask, often as part of role-play, BDSM, or fetish play. The mask could be of various types such as a traditional masquerade mask, an animal mask, or even something like a ninja or superhero mask. Masking can add an element of mystery and excitement to the scene as it hides the identity of the wearer, allowing for greater freedom in expressing fantasies and role-playing. It also adds a visual aesthetic aspect to the video, making it more engaging for viewers.