When the inside of your ass gets itchy.
Glen: Oh boys lets go down to Texas!
John: Glen are you gonna give me a pearl necklace when we get there?
*Glen is frantically scratching the inside of his ass and it appears as though hes fingering his own ass hole*
John: what the fuck are you doing mate?
Glen: FUCK ME I GOT MYSELF ONE OF THE WORST CASES OF HOLE HOCK! FUCK IM READY TO TEAR MY BALOON KNOT OUT AND TREAD ON THAT SUCKER!