User blog comment:PlantyThePottedPlant/Random Topic Blogging II: Electric Blogaloo/@comment-25533515-20120819201055/@comment-25533515-20120819221008

He appeared in three (maybe four) episode briefly in the background. Just go look at previous episode, you might spot him :)

Many fans spectated that he was the writer of the books in Gravity Falls, but now, we know he's not.