A sexual endeavor in which the
woman applies lube to her grundle (aka gooch, taint). The penis is then rammed forcefully into the midpoint of her grundle (equidistant from the anus and
vagina). The gamble that ensues is legendary, in which the penis slides into either the
vagina or anus.
The greasy grundle gamble is irreversible; once fate has chosen a hole, you must stick with it for the remainder of the intercourse.