I'm more prone to blame the wings for the tummy as well.
The rest of it? I think you might have as others have said a house elf or a brownie or other fae that has far too much time on its hands and is playing silly buggers with you.
Leave out some milk and honey and a shiny bauble for it and politely ask that it that if it wants to look at your stuff to please put it back where they found it.
I'd say leave them alone, but they're rather like children in that respect. Tell them "no" and they go straight for it when your back is turned. So I've given up and just asked that they put it back when they're done.
Things still get shifted around (I can see dust trails) but at least they're largely in the same spot it was before they started playing.
Although I'm in a bit of a battle of wills with one over the position of my
buckyball cube. I keep it in the middle of the middle cubby hole in my ikea entertainment center. I keep finding it in the 4th. I keep putting it back and it keeps getting moved again.
I'd ask him to leave it alone but I think we're both having too much fun trying to out-stubborn each other.