Someone who believes DNF is real, never shuts up about how DNF is real, and sends their followers to harass anyone in the fandom who doesn't think DNF is real. Basically annoying toxic people, save for a few truthers who are kind and respectful. We love the kind and respectful truthers here.
"Hey, have you talked to Bella recently?"
"Oh my god no, she's one of those toxic DNF truthers. I'd rather die."