Girls who love bad boys most likely have strongly ancestry from warrior families or warrior clans. Take for example the US where there is a cult of bad boy worship and idolizing bad boys or black men/thugs from the ghetto. The largest ancestry from the US is German & English which have a long history of strong warrior cultures. The Germans had some of the fierciest Germanic warriors which the Romans often called Barbaric and Savage. The genes passed from these Germanic warrior brides are still present in some of today's female population which is why lot of American girls still crave bad boys. I often noticed that the girls who like bad boys often have robust skull and strong defined bone features which are typical of warrior clans and warrior cultures, because bigger stronger bones protect against punches/hits to the face.