They don't merely sell Women & Children to as Sex Slave, they Torture & Brainwash them. Pimps, are not forced into it (although some see it as their only means of survival); they chose the profession for money, sex, and power. Their profession is glorified in gang culture, which is clearly evident in Rap music.
Once in, they're often drunk with it as they now have power over other human beings, with all the money they can have by selling them. It is everything a depraved man could ever want.
You may be wondering why they brainwash them? It is to convince them that they have no hope outside their present state.
Children caught into it, tended to go back, but not because they loved what they were forced into, but because that's the life they ever knew. So when they leave, they have a hard time adjusting to normal life; they cannot keep up with the grades, responsibilities, etc, because they've known only a slave's life. It was certainly abusive, and unspeakably so, but it was the only thing they're familiar with.
That is why you might have heard about abused women go back to abusive men, because that's all they know of love. They don;t know what real love means. Their physical treatment of them is confused with safety and security; and the promise of Pimps assures the returning victims security as they do have wealth.
