Well what Tjf said to me was that supernatural creatures exist, but are rare. I think something like an oni would work. Or something that can at least pass for human or has some kind of form changing ability to enough of a degree to disguise themselves somewhat, I think.
Well, I was thinking something along the lines of: ...Which would probably be too obviously mythical.
I'm not sure how "magical" the world is. But I think that photo would work for a demi-god, or a half-dragon, or maybe a full dragon whose "human transformation" failed, or maybe a human mage experimenting on himself to turn into the strongest mythical beast.
Hmm... I like those last two ideas, if they're possible. Maybe a courtier was trying to turn himself into a dragon (for... reasons) and ended up stuck part-way when the [plot device] he was using failed?
Maybe he had it all planned out carefully only for some kind of stabilizing artifact he was using to get inexplicably stolen by a fox?
That would be okay, though he'd be treated differently by people. I like the idea of a courtier who transforms himself.