It's bad to watch people undress without their permission
Mark was  from a rural area, he was in his 20's and had never seen a naked female in person.
Mark wants to see a naked woman that is not just a picture.
Mark goes to a strip club and sees naked women,  one of whom, Donna he gives a good to.
Jack goes to an all girl's dorm, hides in the bushes and peeks at Donna through a bathroom window as she gets out of the shower.
Mark's curiosity is satisfied and Donna is closer to paying her way through college.
Donna sees him, screams and faints; Jack goes to jail and Donna drops out of college traumatized by the experience.