Stories like this is what make parents think RPGs and CCGs are evil. Silly parents
Not a bad story. It reminds me of something you would come across in Tales from the Crypt or one of the darker Twilight Zones.
Editing aside, I do think that you pulled the trigger on the demon card a bit early. Not sure where I would have put the motives of the guy that sold the card though especially since the story was mainly from Jack's point of view. It's not something that Jack would have known so I may have even left it out entirely. But, it's not my story is it?
Anyway, loved the story despite all above comments. Thanks for sharing.