What we've got here is a...leaf-napper!

The perp: Cali, a sneaky calico whose mission in life is to steal my bestest velvet leaves...

Here's my innocent box-o-leaves...When I'm not looking, she verrrry quietly jumps up onto my worktable and nuzzles around in the box til she finds just the right one. It must be a spray of leaves, preferably expensive ( from Tinsel Traders, of course), and one with some of the leaves cut off. She delicately takes it in her sharp little teeth and stealthily makes off to her lair...on a folded blankie by the window...or under our bed!
She proceeds to wrestle the thing into submission...
I didn't do it!!!!
Further evidence...Here's a close-up of the poor victim, slightly moist with a few tooth marks...

Case closed for now. Leaves returned and replaced with proper cat toy...(not!)...this is the only toy Cali likes, so I do let her play with the wire skeleton that's left over when all the leaves have been cut off. I think she thinks it's a really long, skinny bug!
Gotta love her. And I do!