10. Jack can lose.

Ianto has to admit, fairies are just plain weird. And, apparently, evil. But it isn't the fairies that humanize Jack, it's that Jack loses. Lisa isn't the only one Jack hands over to fate. Just as surely, Jack doomed a little girl to an endless existence. And Ianto is the only one to understand. When he tries to explain to the others what Jack did, he can't find the right words. Only what he can tell Jack. He had to cut the losses.