Arse Hair Demon 

Alternate spelling, "Arse-hair demon": An extremely small, gnome-like creature, with powers of invisibility, who sneaks up on unwary victims, and gives their perianal hair a sharp tug, causing them to shriek, and/or leap skyward, for no outwardly perceptible reason.

Ariel and Deanna were enjoying high tea with the Queen, when HRH suddenly gave a sharp yelp, and leapt from her seat. Royal Guardsmen rushed towards the table, but Her Majesty waved them off, stating, "Bugger off, ya sods, 'twas merely a wee arse hair demon, ticklin' me hindparts."

Arse Hair Demon by Sir Neville W.F.G. Mariner, April 22, 2006

Arse Hair Demon 

Little invisible monster that grabs the hair on a guy's arse when shagging. Pulls the hair back and forth as hard as possible, resulting in the guy increasing his stroke rate to previously unimaginable speed.

Girl 1: "So, you got it on with Andy last night huh? How was it?"
Girl 2: "Andy was such a considerate lover until the point that the arse hair demon entered the room. Then he just pounded the shit out of me."

Arse Hair Demon by Scotsdave April 2, 2006