Sister Peter Marie Reimondo AKA Sister Pete is a Catholic nunn played by Rita Moreno
A nun, she served as the titular prison's lead drug counselor and psycholigist. She opposed the death penalty, supported much of Tim McManus ideology, and cared to help the inmates become better people. She was formerly married, but her husband was killed when he was pushed off a truck by inmate Ron Bebe.
She also was involved in several issues throughout the series involving Tobias Beecher, Chris Keller, Gloria Nathan, Kareem Said, Ryan O'Reily and Vernon Schillinger. She was especially fond of William Giles, a mentally disturbed inmate who solved her husband's murder.