A rancher and his family have a milk cow, and not much else to their name. The milk is the sweetest, toppest grade dairy around.
One day, the rancher wakes up and finds his milk cow dead. Unable to face life with his sole source of gone, he sets up a noose in the barn and takes his life.
The rancher's wife wakes up that same day, and goes to find her husband. When she sees the cow dead, and her husband hanging beside it, she goes to the nearby river and drowns herself.
The rancher's eldest son wakes up, finds the cow, his dad, and his mother all dead. He is approached by a beautiful woman who says that if he can make love to her 10 times in a row, that she will revive his parents and the cow. If he failed, she would kill him.
The eldest son, of course eager, immediately agrees. He doesn't make it, and she kills him on the spot.
The second eldest son wakes up, finds his family dead along with the cow, and is approached by this same mysterious beautiful woman, who proposes the same arrangement. This son, also eager, quickly jumps at the opportunity.
Again, the son falls short and is killed.
The third and youngest son wakes up and finds his family and cow dead, and is approached by the woman.
"Rough day, huh?" She said, offering him the same deal as her brothers.
"So I make love to you 10 times without stopping... and you bring everyone back... What if I make love to you 15 times?"
"Well... I'll bring everyone back, even the cow, and put a mansion where your little ranch is."
"Ok... well what if I make love to you 20 times without stopping?"
Laughing, the mysterious woman says, "Well, I'll give you a great big bag of gold, jewels, and money. So much that you and your family will be set for life."
"Fine, fine... but last question. If I make love to you 20 times without stopping, what's to stop you from dying from it? The milk cow did."