The studio originally thought John Landis was going to cast John Belushi and Dan Aykroyd as Jack and David respectively, so in this AU version we have David Kessler turning into a Were-Aykroyd instead. The story is that the Were-Aykroyd took a liking to David and thought...'hmmm...he's handsome, but he needs to be a bit more Aykroydian.' and used his powers to turn David into a Were-Aykroyd.