How about all the boys that get turned into donkeys? Even the story forgets all about them once they have been transformed.
"Puss in Boots" also has elements of this. When he first inherits the cat, the young man's plan is to make some money by selling its skin to make gloves. His sentient, talking cat. Another version has the master promise the cat a golden coffin upon death, in gratitude for all it has done for him. The cat suspects this to be a lie and plays dead. He is furious when the master instead plans to simply throw his body out the window.