A German guy called Helmut approaches a lady of the night in London .
"I vish to buy sex viz you."
"Okay," says the girl, "I charge £50 an hour."
"Ist goot, but I must varn you, I am a little kinky."
"No problem," she replies cautiously, "I can do a little kinky for an extra £10."
Helmut agrees
So off they go the girl's flat, where the German produces four large bedsprings and a duck caller.
"I vant zat you tie zese springs to each of your hans und knees."
The girl finds this odd, but complies, fastening the springs as requested.
"Now you vill get down on your hans und knees."
This she duly does, balancing precariously on the springs.
"You vill please to blow zis kwacker as I make love to you."
She thinks this even odder, but figures it's harmless (and the guy is paying).
But the sex is fantastic: honking away on the duck caller, she is bounced all over the room by the energetic German. The climax is the most sensational she has ever experienced, and it is several minutes before she has enough breath to say, "That was totally amazing! What do you call that position?"
"Zat," replies the German, "is ze Four-sprung Duck Technique."