there was a time when penthouse stopped publishing nudity (believe it or not). that has changed again recently so there will be no more Penthouse in prison for that reason.
https://www.inmateaid.com/ask-the-inmate/why-can-inmates-receive-penthouse-magazines-but-we-can-not-send-nude-pictures-to-our-inmate#answer
Accepted Answer Date Created: May 17,2021