A person sexually enthralled by a sexual body part swinging freely from a fixed point, as in huge pendulous breasts or long swaying balls. (pendulum+lust)
When a porn actress blows a guy and he cums. She then lets a big glob leak out of her mouth for the camera and instead of dripping off, it swings back and forth from her chin or from the guy's cock.
Man, did you see the sperm pendulum hanging off that girl's chin in that last scene?