Karl is the symbol of conglomerate chocolate manufacturers like Hershey. In the episode "Art of Darkness II: Cocoa", he is seen peddling his products to people on the streets and does his best to force them down people's throats. After encountering Karl, Brown becomes fed up with Karl's inferior products and sets out to produce his own homemade versions. At the end of the episode, Karl is indicted for selling inferior chocolate.
In "Power Trip," Brown visits Koko Karl in a solitary confinement cell in a parody of "The Silence of the Lambs". There Karl informs him of how energy bars do not qualify as health food.
In "Puddin' Head Blues," Karl is disguised as "Auntie Puddin". He is arrested for having jumped bail.