Toki no Tabi

The story centers on a doctor and a girl named Toki, who climb steep mountains and cross barren wastes on their journey together. Even though the doctor can ride on clouds and soar through the sky, the doctor does not lend a helping hand to Toki, only going on ahead of her and stopping somewhere to drink and eat while waiting for her. They have a puzzling way of traveling that nevertheless remains intimate.
(Source: Anime News Network)