The Candy Zombie flesh was a sample of tissue from the Candy Zombies who appeared in "Slumber Party Panic". The flesh was highly contagious, and could turn one into a zombie.
Princess Bubblegum had been experimenting on this flesh during a flashback in "From Bad to Worse,". When Cinnamon Bun came into her lab, stating that he was hungry, Princess Bubblegum dismissed him and turned away, not paying attention to him or the flesh. Upon noticing the flesh on the table, Cinnamon Bun tasted it and took an instant liking to the flesh, eating it whole. Upon eating the flesh, however, Cinnamon Bun immediately grew ill and fell over, turning into a zombie.
- In "Slumber Party Panic," other Candy People ate the contents of the inside of Candy Zombies after smashing them and didn't get infected. This is most likely due to the fact that the insides of the Candy Zombies was the candy they consumed and was not infectious.