Start Running

Three boys were walking home from school one day. All of a sudden, they saw a naked lady sunbathing¹ so of course, they stopped to look. Then, right out of the blue, one of the kids takes off running.
The next day, they see the same lady, and again, the same kid takes off running.
On the third day they stop to see the lady, and she is still there. But this time, before the kid can run away, his two friends grab him by the arm, and they ask him: "What's the matter, don't you like looking at naked women?"
And the kid replies, "Yeah, but my mommy told me that if I look at a naked woman too long, I'll turn to stone; and I felt something getting hard."