A guy goes into a brothel and tells the Madame "I want a tough woman. A strong woman. Got any?"
"Sure" she replies, and calls over this tall blonde unit. The guy gets out a match and strikes it across her tit, but didn't light.
"Nope" he says. "Got anyone tougher?"
"Sure", the Madame calls over a lusty, busty redhead. The guys strikes the match across her tit and it smouldered but did nothing else.
"Nope. Got anyone tougher than her?"
"Okay" the Madame says and calls out this black amazonian wench. The guys strikes a match across her tits and it flares up instantly.
"I'll take her" he says and they adjourn to her chamber. He goes to the bathroon and freshens himself up and when he returns she's naked and on the floor - in the all fours position, with one leg raised up in the air.
"What are you doing?" he asked
"I thought you'd might like to crack open a beer before you start"