Centuries of wealthy Peruvian families sent their daughters off to the Monasterio, where they could rest assured they wouldn't have to do any pesky work. Slowly but surely, the place began to develop a reputation. (The lavish parties the sisters kept throwing didn't help matters.)

Throughout the 18 months we traveled around the world, Señor Pig was a constant. No matter how bad a day we had, he was always cheerful and available for a cuddle. He never minded long travel days, cramped leg space, or frustrating delays. He didn't even mind being placed on a German man's head.

Somebody screams, I'm not sure who. We all start laughing nervously, laughing loudly, laughing to show we're not afraid. Someone is pounding on the elevator call button. We're all clutching each other, groping for one another's hands in the darkness.

An email from Anita asks, in part: "Will you be so kind and give me the address or contact details of that hostel in Cuzco where you stayed. Please? And one more question – why didn't you go for Machu Picchu trekking tours?"

Tim and I have been gathering data on South American toilets for five months now and we have a lot to share. But given my close relationship with them, I feel some of this information needs to be shared sooner rather than later. Not because I want to complain, of course, but for the sake of all those travelers who come behind (so to speak).