"Lollipop" in the context of a porn video tag usually refers to a specific sexual act or prop used in adult films. In this case, it could either mean:
1. A sweet treat, often associated with oral pleasure and foreplay, particularly when it comes to sucking and licking.
2. A dildo or vibrator shaped like a lollipop, often used for similar purposes during sex scenes in adult films. The stick acts as a handle while the bulbous head can be used for penetration.
Note: This explanation might not be accurate if there's another meaning specific to a certain culture or language that was not specified.