A student tries to fix a problem he accidentally caused in OZ, a digital world, while pretending to be the fiancé of his friend at her grandmother's 90th birthday.

Kyuta, a boy living in Shibuya, and Kumatetsu, a lonesome beast from Jutengai, an imaginary world. One day, Kyuta forays into the imaginary world and, as he's looking for his way back, meets Kumatetsu who becomes his spirit guide. That encounter leads them to many adventures.

1999 anime film directed by Mamoru Hosoda