A friend asked us to keep their pet snake "for a little while" and said "don't worry about feeding her, we'll be back before she has to eat again" a month later, I'm worried enough to ask at the pet store how often snakes eat and begin feeding it every two weeks or so and cleaning its cage when needed. This was two years ago. Now they want it back without paying us anything more than a token fee "just to be nice". But we have grown attached and often take it out to handle and carry it. We worry that they will not be able to care for it. Do we have to give it back or have they de facto given up ownership of the snake ?