Say, I forgot I have another drawing of Zadoc. Actually, it’s a looser rendition of the same drawing–and it’s on a page with some sketches of Yippy, definitively establishing Zadoc as a denizen of the Scrappyverse. As for the gruff kid in the cap, he looks like the bully from Sunday Clothes. A cartoon which Zadoc doesn’t appear in.
I’ll let you know if I come any closer to figuring out just who Zadoc was.