This is a real and existing Treehouse. My wife and I had a nice long weekend on a holidaycamp, in the middle of forests and heath. Perfect weather, nice long walks, beautiful colours. We had a nice small luxury cottage, surrounded by trees and squirrels. But elsewhere on the terrain there was this beautiful wooden treehouse, for rent, but not in our league.
I forgot to take water for painting. But I still had a waterbrush, so I washed out the ink before it was dry.