Emotionless Girl/Playing With

Basic trope: A girl who almost never shows any kind of emotion. "Bob: "You know, Alice, you seem very cold and unfriendly. What's up with that?""
 * Played straight: Alice never smiles.
 * Exaggerated: Alice's face is frozen solid.
 * Justified:
 * It's the only way she can control herself. If she emotes, bad things happen.
 * She's very deeply hypnotized.
 * Or she's a robot of the non-ridiculous kind.
 * Or she has brain damage making emotion impossible for her.
 * She's been trained to and is afraid to drop the charade for fear of consequence.
 * The Sociopath.
 * She suppresses her emotions because she thinks women should be stoic.
 * Inverted:
 * Hysterical Woman
 * Stepford Smiler
 * Subverted:
 * The emotionless girl bit is all a front. When she meets a new friend and gets to know him/her well enough, Alice opens up.
 * AKA she's a Sugar and Ice Personality or a Defrosting Ice Queen
 * Double Subverted:
 * ...then he/she dies, and Alice goes back to the way she was.
 * She was consciously trying to be expressive, but eventually decided that it didn't work for her and settled back into her comfortable patterns.
 * Parodied:
 * Alice's friends all try to get her smile or laugh at something.
 * Alice's friends challenge her to a Staring Contest.
 * Deconstructed:
 * An "origins" episode of a TV show or superhero comic shows that a ton of nasty stuff happened to Alice in her life, and that she's very emo about it. She suffers from depression and has attempted suicide in the past.
 * She's born like this and it alienates the hell out of her (both in-story and in the viewers) due to the fact that she will feature stoic reactions to what should be emotional scenes (violent murders of relatives, heartwarming reunions, etc.) She may even justify it by asking something like "Why should I feel emotions to these scenes when they are so common?"
 * Her emotions are deliberately suppressed (by magical or medical means) because she's Ax Crazy with emotions.
 * Reconstructed: She decides to seek some therapy, but still doesn't turn into a ball of smiles.
 * Zig Zagged: See also PMS. She goes through this trope, Yandere, Sugar and Ice Personality, and Tsundere all in a matter of minutes.
 * Averted: Alice smiles and laughs at stuff.
 * Enforced: Pretty much anything by Joss Whedon, especially Dollhouse.
 * Lampshaded: Alice has a very sadistic mindset and the stuff she's laughing at involves people dying and really bloody fights or Dead Baby Comedy.
 * Invoked: Alice actually sees a fight or a killing in progress and decides that this trope is the best response.
 * Defied: Fake smiles.
 * Discussed:


 * Conversed: "I'm in a staring contest with Yuki Nagato!"
 * Played For Laughs: Alice is unphased by the bizarre goings-on around her or causes embarrassing situations for other characters. She walks in on her friends changing to ask what they want to eat, walks across the rickety Rope Bridge without a second thought, and asks the giant monster where the nearest grocery store is.
 * Played For Drama: Alice really wants to experience emotions, but because she's a Barrier Maiden, she can't risk showing them without potentially causing massive destruction. Characters around her aren't necessarily aware of this fact, and constantly try to cheer her up or otherwise make her emotional.

Would it kill you to smile a little bit as you go back to the main article!?!