I prefer your smiling face
At Hime-chan's birthday party, Erika is filling in for her. She still can't transform back. Erika said that her grandfather, the strongest person in the land of magic, might be able to help Hime-chan. Later Sei told Daichi that that only way Hime-chan could return to her normal body was if she died.
Aired 05/02/1993EP 18 - I prefer your smiling face
Hime-chan no Ribbon
Erika, the princess of the Magic Kingdom has come to Earth in order to find a human girl who looks just like her. That girl turns out to be Himeko Nonohara, a tomboy's tomboy. Erika must give Himeko a magical item she has created in order to prove her worth as a successor to the crown. Himeko must test this item, a hair ribbon that allows her to transform into any other person she sees, to see if it is worthy. The series follows Himeko's adventures and her budding romance with Daichi, the boy who discovers her secret.
(Source: Anime News Network)