King Tommen's cat, Ser Pounce, only appeared in one episode in the fourth season of Game of Thrones ...
... but he immediately became a favorite of fans who were presumably desperate for something cute to latch onto in the vast darkness of the show's various plots. There were memes, parody Twitter accounts, relentless demands for updates on the fate of Ser Pounce. Theories that the Starks would warg into Ser Pounce to get to Tommen or that Ser Pounce was a descendant of an important cat described in the books that may or may not be a vessel containing the warged spirit of Rhaegar's daughter or a completely different kind-of Targaryen who is only briefly mentioned on the show. It was a whole thing.
On the set, however, he wasn't nearly so popular, and if you've ever tried to "train" a cat, you know why. Soon after the episode aired, writer Bryan Cogman reported to the Making of Game of Thrones blog that "This is probably the last time you'll see Ser Pounce because filming with a cat is a nightmare," even insulting the exalted feline as a "sumo wrestler cat." That's right: He hated a cat so much that he called it fat for everyone to read. "Natalie Dormer wanted to kill me," he continued enigmatically, and the Margaery Tyrell actress later explained in a Reddit AMA that "Ser Pounce was a bit of a diva that day, he didn't want to stay on the bed, he was very difficult to work with." Years later, the showrunners were still complaining about the damn cat, telling Entertainment Weekly, "That cat was really not fun to work with. There's a reason the phrase 'like herding cats' came into existence ... Dogs generally do what you ask them to do if they're smart and well trained. Cats have their own agenda."
In fact, they hated him so much that they killed him. The fictional character that is. "Cersei hated the name 'Ser Pounce' so much she could not allow him to survive," David Benioff told EW. Neither D. nor D. elaborated on Ser Pounce's manner of death, but it was apparently "so horrible we couldn't even put it on the air," although Dan Weiss joked that "If you buy the super-extended, super-charged Game of Thrones box set that comes out, the death of Ser Pounce will be in there. Just one whole episode devoted to the death of Ser Pounce." There was nothing stopping them from telling us that Ser Pounce escaped war-torn King's Landing on a merchant ship headed to the idyllic Summer Isles to spend his days lazing in the sun, safe from murderous royalty of all stripes, but no, they couldn't even let us have this.
Top image: HBO