Sex Crimes looks at the cyclical movement in Europe from implicit sexual tolerance to repression, to sexual liberalization and open tolerance. Cultural historian William Naphy considers the whole gamut of sexual activity which could result in a criminal prosecution and, usually, execution. He considers those types of behavior considered criminal but "natural" (adultery, bigamy, fornication, rape, prostitution), "unnatural" sex (masturbation, incest, child abuse, same-sex relations), and finally "inhuman, unnatural" sex (bestiality, sex with Satan). William Naphy emphasizes the modernity of the past in its attitudes while highlighting those areas where socially constructed attitudes most differ from the present day.