23rd Oct: It's time for the second TV Tropes Halloween Avatar Contest, theme: cute monsters! Details and voting here.
Characters don't just stand there and calmly observe the world around them. They laugh and cry and scream in reaction to the things that happen around them. These In-Universe reactions are catalogued here. Compare Audience Reactions, Body Language, Surprise Tropes & In-Universe Examples Only. Contrast with Apathy Index.