Enslavement is an ever present risk on Barsoom, especially to women. Captives of war are enslaved and kidnappers sell their victims it is thus a condition to which any Barsoomian, regardless of rank, may be reduced at any time. The attitude and behavior of slaves towards their masters seems to depend on their treatment; if treated humanely and with dignity as in Helium the slave may take pride in his service and be loyal to his master. If treated poorly he or she will take their first chance at freedom and/or turn violently upon their masters.
Female slaves face the extra threat of sexual abuse. Many Barsoomian women prefer death to concubinage but others lack either the opportunity or the will to commit suicide and are forced to live as sex toys of their masters. In some cities, such as Helium, the persons even of slave women are sacrosant and they need have no fear of rape. Women passionately in love with men already mated have been known to give themselves as slave attendants in return for the privilege of staying close to him, an arrangement that must be more than a little uncomfortable for the man and his wife.