1. (v) The willful self-insertion of a spiked, barbed, or pointed object into one's rectum for the purpose of sexual gratification or personal accomplishment.
2. (n) The act of committing a Prickly Stephen.
It was pretty gross when Thistlehair decided to Prickly Stephen that fistful of premium cutlery up his ass, but it was even worse when he pulled it out and put it back in the package.