Farts and crafts. I'll leave now.
Ok, maybe not "imaginable," but certainly grosser than anything you've imagined today. I feel pretty bad for the cat, except for the fact that he continued to play with his butt-string. That's just reprehensible, you adorable little kitty. Gross. Gross kitty! Animal confessions may be a meme belonging to 2013, but we can all agree that this cat deserves special shame.
Note to owners, if this ever happens to your cat, do not pull the string out. Let it come out on its own, even though that's really gross. Intestines are have a lots of twists and turns, and strings try to move in a straight line when you pull on them.
(by Johnny McNulty)
Sources: redditor ipostscience