A person refuses something they would normally take, and it tips off everyone else that something is wrong.
Alice loves ice cream. She adores ice cream, in fact. She eats it all of the time. Well, Bob decides to offer her some ice cream, for whatever reason. However, Alice refuses ice cream for once, and Bob immediately knows something is wrong. Well, Alice has just been dumped by her boyfriend, and she is so depressed that she doesn't even want ice cream. This need not always apply to the 'I'm so sad' circumstance. Other things such as a medical reason (such as a person hiding diabetes refusing an all time favorite sweet) or a frightening experience (such as a woman refusing a favorite perfume because of some earlier, traumatic experience that was recent) can also be used. Real Life example: Dogs that are frightened will sometimes refuse to eat what would usually be their favorite food i.e. prime rib, steak, a treat, etc. Usually Played for Laughs, especially if used in the case of a Genki Girl or The Stoic. Expect to find it in chick flicks. (I apologize if this is already a trope, as I could not find it upon looking it up.)
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