I don't know what this thing is --- it's a woody shrub that's growing practically right on top of one of the maple trees in our yard. It's very sparse --- only a few branches --- compared to all the free-standing shrubs we have.
Here are some pictures that show more of it, and how it leans against the trunk of the tree:
We also didn't plant this --- either the people who lived here before us did, or it volunteered, grown from a seed misplaced by a bird or squirrel or something.
It's my favorite of all our plants. I'd like to paint it sometime.