Cole is a boy in high school. He runs cross country, he sketches, he jokes around with friends. But none of this quite matters next to the allure of sex. "Let me put it this way," he says. "Draw a number line, with zero is you never think about sex and ten is, it's all you think about, and while you are drawing the line, I am thinking about sex." Cole fantasizes about whomever he's looking at. He consumes and shares pornography. And he sleeps with...