In essence, fucking the asscrack. In some areas of the nation this term is known as "Butt Sex Light".
Origin: 16th Century Dutch saffron merchants.
Though Chad's initial thoughts were to stick it in the stink, he pussed out and instead shot the gutter. (It should be noted, that when it was all over Chad was in a position to return home to his wife without any obligation to wash his genitals.)