Mr. Jingles She was a mouse in the Green Mile, that was named correspondingly. Everyone felt attached to her. When Percy nearly killed it to make a prisoner suffer because of it, John Coffey saved it.
After his death Paul Edgecomb took care of it in memory of John Coffey. 63 years have passed since then and he is still alive because of John´s actions. It forces Paul to wonder, when he will die, if he lived so long.