Make her beg.

"Don't make me beg," she says? You were about to hand over the cash, but you might as well get some entertainment for your dollar.

"I don't know," you say, studying the the bills in your hand like they're the last you'll ever see. "I really need this money for, um, textbooks. Yeah."

The hope flickers out of Amanda's eyes, and her coy smile droops. She still holds the hem of her skirt over her waistband, though.

"Oh, please mister! We really need the money! The Home can't even afford to buy us new underwear!" Amanda thrusts her pelvis forward for inspection. Looking closely, you see her panties are threadbare. They're especially worn right below her little blond mound, as if subjected to frantic and frequent friction. Her wetness makes the thin white fabric transparent, providing a pink window to her puffy pussy.

"We have to wear these donated clothes. Look, they don't even fit!" Sure enough, her outfit looks like it was sized for a girl about six inches shorter. The sweater, while generously proportioned, still strains to contain the sheer girth of Amanda's boobs. And the flap of a skirt Amanda is holding up doesn't even reach her exposed belly button.

"I'm not even on the cheerleading squad, I can't wear these to school. You should see the clothes I have to put on. Everyone knows we're poor, and thinks I'm a slut." Amanda breaks eye contact and looks away, she is so embarrassed by the thought.

"And the Home is so overcrowded. There aren't enough beds, or blankets. And they can't afford to pay the bills. We have to double up, two to a bed to save on heat. The showers don't have curtains. Do you know how hard it is to get any privacy? I only get a minute in a bathroom stall to -- y'know..." Amanda runs a hand over her soaked patch of panty. Well, that explains the wear and tear.

"Please mister, please help us out. The offer still stands. I'll play with myself. You can watch. I'll take off my panties and you can get as close as you like. I'll do anything to myself you tell me too, no matter how nasty. I'll even stick my fingers in there. I think I can even fit in three."

Amanda starts to babble desperately. The poor girl has such a tame notion of what constitutes "nasty". A less scrupulous fellow could certainly think of ways to take advantage of this situation.