During the end of the season 4 finale of Game of Thrones, after “The Hound” has been defeated by Brienne of Tarth, he lies bleeding and dying and wants Arya to finish it and kill him. At first he tries to taunt her into it, and then just asks her to kill him:
Do I have to beg you? Do it! Do it! Do it!
To which Arya just stands up, takes his gold and leaves him dying slowly. But I wonder why she didn’t do him this favour. I see that she became gradually more hardened during her odyssey, but it also seemed she took a little bonding with “The Hound” during their journey. So why was Arya reluctant to kill “The Hound” and left him to his mortal agony?