"Like anger," said Skulduggery, "and hate, and rage. Jealousy, to an extent. Frustration. The idle desire to hurt somebody for something they've done. The less idle desire for revenge. His gist encompasses all of it, and it's up to Anton to keep it on a leash. That's why he won't break his own rule of neutrality within the Hotel, even if his worst enemy were to cross the threshold."