[Originally posted at Ana Mardoll's Ramblings.]
I once thought of having a story centered around a sidekick who is convinced that they're all living in a work of fiction.
He kicks into frantic action when the obvious main character meets his perfect mate. His reasoning is basically that their life definitely seems to be episodic. In an episodic story like theirs if the main character meets someone who is a pretty good match there's some hope that they'll go their separate ways at the end, or they'll end the episode together and separate before the next episode, but when main character meets the perfect person she'll be dead before the episode ends. (Or possessed, or turned evil by unpleasant circumstances, but most likely dead.)
She's smart, funny, beautiful, she gets along with everyone, everything is idyllic when she's around, so sidekick is completely convinced that she's too good to live.
Took me forever to discover that there is a trope for that.
Anyway, the story would be the character focused not on saving the [whatever]/stopping the [whatever] (that's a foregone conclusion in his mind) but on identifying and preventing any potential threat to the main character's love interest.
In the end everyone else would conclude that his paranoia had managed to help her survive an unlikely series of should-have-been-fatal events. He would conclude that by defying narrative dictate he had successfully shifted her into the category of recurring character, possibly even main cast. And I'm thinking he and she end up as best friends.
Don't have anything else about the story figured out, though I do know that I want the supposed-to-be-temporary love interest to be extremely competent to the point that the only reason she needs saving is that the narrative is actively trying to kill her. Also I don't want it to be actually be saving so much as providing assistance. She wouldn't need saving so much as support.