Sincerity is weird, she looks dubious of it but... she doesn't have any evidence to doubt it either. Try. She has to at least try, right? Try to trust.

Baby steps.

"Oh, I think between who I am, and where I am, there will always be more bullshit." She's a seventeen year old ripped away from her whole life, into a world regularly in peril, with magic and monsters. Something can, and will, always go wrong.

Still, she smiled with that last line, waving lazily as she started down the side of the building. Like that's a perfectly normal way to leave.