The Un-Smile/Playing With

Basic Trope: A usually stoic character tries to smile, but it ends up being creepy.
 * Straight: Bob, who has never been seen smiling, finally does, but it heads straight into the Uncanny Valley.
 * Exaggerated: Bob, who has never been seen smiling, finally does, but his smile is High Octane Nightmare Fuel.
 * Downplayed: Bob, who has never been seen smiling, finally does, but it looks somewhat creepy until he gets it under control.
 * Justified: Bob, while attractive in real life, is just not very photogenic.
 * Bob can smile just fine when he has something to smile about. Faking a smile, on the other hand...
 * Inverted: When She Smiles.
 * Subverted: Bob slowly smiles, and it seems to be heading into the uncanny valley, but becomes cute smile.
 * Double Subverted: ...Then it keeps going into Nightmare Fuel.
 * Parodied: Bob's Smile is so horrible to look at, everyone around him loses bladder control.
 * Deconstructed: Bob was in a horrible accident years ago, and the facial nerves and muscles didn't heal right.
 * Reconstructed: There is nothing that Bob wants to smile about anyway.
 * Zig Zagged: Bob's smiles can either be this or When She Smiles, often without rhyme or reason.
 * Averted: Bob's smile is in no way creepy.
 * Enforced: ???
 * Lampshaded: "Is that a smile or did you lose a fight with a weed whacker?"
 * Invoked: "We want to use Stoic Bob in a joke. I wonder how..."
 * Exploited: The Five-Man Band uses Bob's creepy smile to distract a guard so they can sneak in somewhere.
 * Defied: Bob just smiles.
 * Discussed: ???
 * Conversed: ???
 * Played For Laughs: Almost always.