A sack bearer is a peasant occupation little used in modern times. The sack bearer, or sack bearers as they often worked as a pair, were in charge of their employer's or master's scrotum. Their primary purpose was to ensure that no stress or tension was caused on the testicles and connective tissue. To accomplish this task, the sack bearers would all all times cradle the scrotum with their hands, keeping the testicles inside warm and protected.
The logistics of having a sack bearer takes time and effort to work around. Have one, or perhaps two, sack bearers at all times attending to one's scrotum can make day to day life hard to maneuver even with the smallest of sack bearers.