Neil Gaiman is a popular author of both traditional and graphic novels. He has blogged about his affinity for Coulton's songs and his delight at attending the Dec. 6, 2007 Minneapolis show.
When Gaiman's book signing conflicted with Coulton's Manchester, UK: 2008-10-29 concert, Coulton ducked out of his sound check to play a short set at the signing. Gaiman reciprocated by going onstage at the concert to read a verse of "Creepy Doll" in a creepy voice, and play the tambourine (with guidance from Paul of Paul and Storm) for part of the song. He joined Jonathan (with Paul and Storm) on stage for "Creepy Doll" again during the St. Paul, MN: 2009-02-27 concert.
Gaiman is also shown in the video of the opening credits for "Monkey Shines".