Choke 'em(1996)

Five trainees, representing different branches of the US defense, are sent to special training. Gino, as the drill instructor, gives them their orientation in the barracks, while they're only wearing drawers. There they will spend the next eight weeks in hardcore training, with no contact with the outside world, especially women. So after being sent to their bunks, the D.I. goes into his office at the end of the bay and pulls out a girlie magazine. Meanwhile each trainee masturbates on in their own bunk. Eventually the D.I. sees what's happening and stops them. At least until the next morning, when they form up around his D.I. hat and ejaculate.