The ghost has the unusual power to hide inside of solid material but is unable to simply pass through it. It becomes "stuck" to the surface that it enters through and must eventually return that way. However, it can send its presence and acute senses through solid material an indefinite distance, perhaps even across the entire planet. Secret meetings should take place at sea or in the air in order to assure privacy.
The ghost communicates via writing upon its body. If you care to sift through the question marks and unscramble the letters you find, they will spell, "Boo, boo, boo, I will eat you."
The original is for sale at ETSY and the prints can be bought at FineArtAmerica.