When I was in the Maryland National Guard, a female ROTC cadet appeared in a Playboy Magazine college women feature. She was "asked" to resign from ROTC and from the Guard.
A 1st AD soldier appeared in Playboy a few years back. She had apparently taken the photos while in the military and they were published after she got out. The Army was mad, but apparently it was too much trouble to bring her back to active duty in order to punish her, so they let it go.