And it is this:
"Fenrir did nothing wrong."
If I get a response ranging from 'huh, you've got a point', to 'heck yeah! Fenrir's the best!'. I'm am (hopefully, optimistically) dealing with someone who takes inspiration from Norse culture and mythology to encourage them to examine and challenge injustice in the world. Hopefully someone that may have even considered that police and prison abolition are needed to right enormous amounts of injustice. (TL:DR; Fenrir's story is one about him being imprisoned on account of a prophecy that he'd 'one day' destroy the world. Then ultimately breaking free at Ragnarok to fight and eat the Gods who committed that injustice.)
If I get a response of 'no, he was like the Christian devil!'; best case scenario I'm dealing with someone who's barely scratched the surface of knowledge on the subject and just needs some education. Worst case scenario, and the safer one to assume, I'm dealing either with an outright fascist type or a liberal who'd tell me off for saying the fascists deserve to be punched in the face and them some.