So I like Edward (shout out to my secret Santa last Christmas for the EG Fantod tarot cards) and I saw your post, which intrigued me. So... I googled and found nothing, then found that Hoo is "used chiefly to express an emotional reaction (as of surprise or triumph) or as a call" so maybe the little dude is saying "hoo' because he lost that piece of paper that is flying up into the sky?
sorry dude i wish your hard detective work didn't have to go to waste! but its from gorey's "the untitled book" which is just a bunch of boiling hot nonsense for no reason other than edward gorey was a wild son of a gun and we love him for it
















