story of metamorphosis; transformation tale
A narrative genre or story centered on physical transformation, often found in folklore, mythology, or fantasy.
Kafka's "The Metamorphosis" is a famous transformation story.
Many Japanese folktales are transformation stories in which animals become human.
Compound of 変身 (metamorphosis) and 譚 (tale, story). 譚 is a literary suffix used in words like 冒険譚 (adventure story) and 怪奇譚 (mystery tale).