(CNN) -- Felipa Fabon waits outside a local fried chicken restaurant in Manila. Crouching near to feral cats and rubbish bins, she isn't there to meet friends for dinner but to search through the diner's trash bags.
"I'm sorting the garbage, looking for 'pagpag'," she says.
In Tagalog "pagpag" means the dust you shake off your clothing or carpet, but in Fabon's poverty- stricken world, it means chicken pulled from the trash.
Pagpag is the product of a hidden food system for the urban poor that exists on the leftovers of the city's middle class.
Fabon is the merchant and pays the trash dealer just over a dollar for tonight's supply of garbage and scraps.
In the dim haze of the street lights, she holds up a half-eaten chicken breast.
"This one, this is meat," she says. "Now what we do at home is clean it, put it in plastic, and then I sell it in the morning. It's very easy to sell because it's very cheap. People in my neighborhood want very cheap food."
"If it's mostly bones, it's 20 pesos ($0.50) per bag," she says.
After bagging up the chicken scraps she heads home to Tondo, a neighborhood infamous in the Philippines as one of the poorest slums in Manila.
At dawn, about six hours after Fabon first got her trash delivery, she begins to divide up the pagpag.
Fabon sniffs the chicken, which she says has a bad, sour smell. She's disappointed that she only has five bags to sell this morning that will sell out in just minutes.
"Pagpag!" Fabon calls out, as she walks through the slums carrying her small cart.
Morena Sumanda, a 27-year-old mother of two, is the first customer.
Sumanda lives in a shanty that sits on top of one of Manila's biggest garbage dumps. She doesn't have the 20 pesos to pay Fabon until her husband comes home that evening. For him, 20 pesos is full day's pay, says Sumanda.
Sumanda's toddler son, Nino, wails as she first washes the chicken, heats the pot and adds vegetables to the pagpag, which is mostly bones.
"Sometimes it comes from the garbage," she says, as she hands a small, half-eaten chicken wing to her son.
Sumanda, and others like her, have no other choice but to eat pagpag, says Melissa Alipalo, a social development specialist and a volunteer at the Philippine Community Fund (PCF).
"It is a private humiliation of the poor to have to eat off someone else's plate. But it's a survival mechanism for the poorest of the poor," she says.
The NGO is based in Manila and has built an elementary school in the heart of the Tondo slums.
PCF's school educates 450 of the most poverty-stricken children in Tondo, with the aim of freeing families from poverty. The school survives on donations and provides students with two meals a day.
Maria Theresa Sarmiento, PCF's manager of health and nutrition, says that when the school first opened she was treating children with a range of illness and disease.
"Even though they cook the food, the disease is still there," she says.
Sarmiento says that parents know pagpag is not a good source of food for their children, but that they don't have any choice.
"They're being pushed to do that thing because they don't have enough money to buy the food that they should prepare," she says.
For Sumanda this is all that she can afford and it's better than nothing.
"By the mercy of God, this is enough," she says.