The origins of the 15, 30, and 40 scores in tennis are believed to be medieval French. It is possible that a clock face was used on court, with a quarter move of the hand to indicate a score of 15, 30, and 45. When the hand moved to 60, the game was over.
Tattoos placed over bones and tendons (spine, neck, back of ankle), on body parts with relatively little padding (feet, hands, joints), and anywhere with loads of nerve endings (nipples, fingers, face) will be the most painful.
