Fan Casting Unreliable Narrator in Sort by Tropes

In most narratives, there's an element of trust that the person telling you the story is telling the truth, at least as far as they know it. This trope occurs when that convention is discarded. The narrator's facts contradict each other. If you ask them to go back a bit and retell it, the events come out a little differently. It can be like dealing with a used-car salesman — there's a real story in there somewhere, but you're left to piece it together through all the lies, half-truths, and mistruths.