Klingon Arse-Pinch
The name for a sudden tug of the hair in the perianal region, often caused by the accidental shifting of an undergarment; also, to surprise someone by giving their perianal hair a tug; can refer to the cause behind a person unexpectedly yelping, or leaping to their feet, for no outwardly apparent reason.
Karen and Soneli were quietly watching TV, when Soneli leapt to her feet with a shriek, as if she had received a vigorous Klingon arse-pinch.