Many people have felt all of a sudden a strong crush on a person they literally saw the first time in life and knew little or nothing about. In the ancient times, this unusual romantic emotion felt for a totally stranger person along with the strong desire to posses sexually that person was known as "Cupid's love arrow ".Today ,we call this "chemistry" or " love at first sight ". This phenomenon can happen equally to both sexes, males and females (sometimes two people of opposite sex may experience this at the same time), even to those who deny the possibility to be struck by this kind of "madness" , in their conception.