Women Prison: Vigilante Justice (1978)

Naomi is sent to prison in place of her brother, who is involved with a violent gang. There, she experiences various forms of vigilante justice at the hands of the sexually frustrated female inmates. From being tortured with leftover food to being stripped naked and forced to crawl around and lick the genitals of other female inmates, she endures insidious sexual abuse. To make matters worse, the female guard is a lesbian. Then, a virgin woman whom her brother had saved arrives in the communal cell, now a depraved prostitute. When Naomi learns that her brother was killed by a gang leader, she seeks revenge upon her parole...