Pen pals are people who communicate with each other through letters, emails, or other forms of written communication. The crossword solutions for the term 'pen pals' include PIGS (4 letters), cellmates (9 letters), SWINE (5 letters), inmates (7 letters), CONS (4 letters), felons (6 letters), OINKERS (7 letters), and PRISONERS (9 letters). All of these terms refer to people who are incarcerated in some form of correctional facility.