Perfect! Shapeshifter he'd definitely smell and I'm imagining demonic nature he'd be able to pick up too, he's seen an awful lot of other supernatural creatures in his own world (especially magic users) so it wouldn't be too much of a stretch. I'll not tie it down to a specific scent but he'll notice something like an other-ness

All those regular scents work well too and I'll keep them in mind if/when threading.

And yes the emotional state one is definitely my favourite, I understand if its threaded out it can go one or two ways.

Thanks for the information!