What video is this from?
The biker has a sweet hairy ass too! Just to sayThis is a hot one. You can see sweat dripping off the top starting around 8:20-8:30
Biker initiates his twink in a motel
Besides the exertion a man exerts during sex, and maybe the temperature of the room, sweat is to be expected. In the animal kingdom animals sweat ("must") to let others of their species know that they are in heat and ready to mate. Man is no different and it's totally fucking sexy!