During the Greek, Roman and Byzantium empires many males were turned into eunuchs through castration for a number of reasons, often at birth or early childhood. With a extremely high priority to religious life, prestigious families with multiple sons would often castrate the youngest male thus preparing and directing him into a life of celibacy dedicated to God(s). Other families of "lower status" would also choose this method to prepare a son for a career as a bodyguard to important families and/or women of the day (no risk of affairs). Also hostile takeovers of royal imperial positions would often see the "new ruler" castrate all the male heirs of the deposed ruler in order to end the blood line and thus limit the number of future claimants to the crown (especially during the Byzantium empire in the years prior to the 1st crusades 700AD - 950AB).
There were 10s of thousands of these "men" throughout history. None of them ever beat-off.