Quite how this unfortunate rat met its end or indeed what it was disturbing (I suspect a little more than a conversation) I know not but I do like the story.
This particular picture (above) by Toulouse-Lautrec in 1899 called En Cabinet Particulier (1899) shows one of these tête-à-tête suppers at the Rat Mort. The woman Lucy Jourdan wears an elaborate domino with a hood; her companion, a Baron, in formal evening attire, has turned his head so that his features are invisible, cut off by the edge of the canvas.
The Rat Mort - where champagne flowed and much furtive love making went on behind the thick curtains of little private alcoves.
I'm sure the rat, had it lived could have told a story or two.
In 2013, the Rat Mort is a bank. So, still full of rats then!