“Unfortunately, you may have to delay your plans for sororicide a bit longer. Gabriel Lightwood is downstairs, and I have two words for you. Two of your favorte words, at least when you put them together."'Utter simpleton'?" inquired Will. "'Worthless upstart'?"Jem grinned. "'Demon pox,"' he said.”

“I was just thinking of bundling up Cecily and feeding her to the ducks at Hyde Park," said Will, pushing his wet hair back and favoring Jem with a rare smile. "I could use your assistance." "Unfortunately, you may have to delay your plans for suicide a bit longer. Gabriel Lightwood is downstairs, and I have two words for you. Two of your favorite words, at least when you put them together.""'Utter simpleton'?" inquired Will. "'Worthless upstart'?"Jem grinned. "'Demon pox,'" he said.”

“Demon pox, oh demon poxJust how is it acquired?One must go down to the bad part of townUntil one is very tired.Demon pox, oh demon pox, I had it all along—Not the pox, you foolish blocks,I mean this very song—For I was right, and you were wrong!""Will!" Charlotte shouted over the noise, "Have you LOST YOUR MIND? CEASE THAT INFERNAL RACKET! Jem—" Jem, rising to his feet, clapped his hands over Will's mouth. "Do you promise to be quiet?" he hissed into his friend's ear.Will nodded, blue eyes blazing. Tessa was staring at him in amazement; they all were. She had seen Will many things—amused, bitter, condescending, angry, pitying—but never giddy before.Jem let him go. "All right, then."Will slid to the floor, his back against the armchair, and threw up his arms. "A demon pox on all your houses!" he announced, and yawned."Oh, God, weeks of pox jokes," said Jem. "We're in for it now.”

“Will: Have you ever seen what happens to someone with demon pox? First it lies dormant. One begins to turn yellow and green. Then the swelling sets in -Jem: THERE IS NO SUCH THING AS DEMON POX.”

“Astriola. That IS demon pox. You had evidence that demon pox existed and you didnt mention it to me! Et tu, Brute!' He rolled up the paper and hit Jem over the head with it.”

“And maybe it would have bitten you in half," said Will. "What you are describing, the transformation into a demon, is the last stage of the pox.""Will!" Charlotte threw up her hands. "Why didn't you say so?""You know, the books on demon pox are in the library," Will said with an injured tone. "I wasn't preventing anyone from reading them.""Yes, but if Benedict was going to turn into an enormous serpent, you'd think you could at least have mentioned it," said Charlotte. "As a matter of general interest.”