Be warned: Below is an obscene joke, that makes fun of other nationalities and assumes that prostitutes actually can enjoy being victimized.
But it does have an advertising angle, so I thought: WTF? and posted it. Now please don't scroll down, unless you're not easily offended.
Still here? Ok, HWG:
A german man approaches a prostitute and says "i vish to buy sex vith you". "ok" says the girl "but it'll cost 20 an hour". "ist good, but i must varn you i little kinky". "i can do kinky" replies the lady of the night.
They then walk back to the girls flat where the german produces from his bag four large bed springs and a duck caller. "I vant zat you tie ze springs to each of your hanz und kneez". The girl finds this strange but complies and ties the springs accordingly.
"now you vill get on your hanz und kneez" says the german. She duly does this balancing precariously on the springs. "You vill blow on zis kwacker as i make ze love to you".
She finds this odd but thinks it's harmless (and he's paying). She finds the sex is fantastic as she is bounced all over the room by the energetic german all the time honking on the duck caller and she comes to the greatest climax she's ever known.
It's a few minutes before she can muster the breath to ask "That was amazing. What do you call that position?"
"Ah" the german replies "zat is called ze.........."
......wait for it
"four-sprung duck technique!"