Auto-erotic stimulation of the anus while driving a pickup. For a traditional Silfen, the fingernails must be cleaned with the edge of an incisor tooth. Extra style points awarded if performed while stopped in traffic and for simultaneous performance with spouse.

the thing that you don’t have when you’re phones percentage is over 20

Auto-erotic stimulation of the anus with one or more fingers while driving a pickup truck. For a traditional, or "urSilfen," the same fingers should then be used to pick crusty boogers out of an extremely hairy nose and the fingernail(s) should be cleaned using an incisor tooth. Extra points for simultaneous perfomance with spouse.