its saying used to describe someone greedy ...theres a story of a dog who had a torta and all the other dogs wanted a piece but he didn't want to share so he took his torta near the river to get away. he put the torta down and saw the reflection of it in the river. thinking it was another torta he jumped in but the rivers current took him down stream, so the other dogs found his torta and ate it. there for he was left without anything. the saying is used alot when a guy is playing to chicks, they find out and he's left with nothing