What the hell is going on in this picture?

My pen pal in New York sent this image to me today. I'm flummoxed. Who is the small child? Who owns the feet behind him? Are those tame rats? They look wild to me, and quite large, which would make them city rats like you see in Baltimore or New York. If they're wild why is the owner of the feet letting the tiny child so near them? What is the vat full of?

The worst idea that ran through my head is that someone is making cheese. Rat cheese. Barftastic.