Part of Anime Tamago 2018.

Rikotto, Zuzu, and Paroru are intelligent furry creatures who believe more than anything that the world outside their island is too dangerous to explore. Despite this, Rikotto and Zuzu long to see the world that produces the mysterious objects that wash up on their shores. After a particularly exciting find, Rikotto convinces Zuzu to build a boat, and they set sail across the sea with their reluctant friend Paroru in tow. At first, the trio finds the foreign land beautiful and exciting, but they are overwhelmed when they come across a bustling city of humans. When Rikotto and Zuzu get captured by a circus ringleader who intends to put them on display, Paroru has to decide what fears he is willing to face for his friends.

Hundreds of years after the 20th century, nature and the ecosystem have been devastated due to use of nuclear and biological weapons. Most of the Earth has been contaminated and is collapsing into ruin, and a great majority of plants and animals are now extinct. The world heads to the "Big Six," the sixth mass extinction event. Humanity built cities in the sky, migrating the endangered species of animals and plants there. Over many years, the animals evolved in these isolated cities. With artificial genetic crossbreeding, they acquire language, bipedality, and build a life and civilization for themselves free from want. No one thinks of the world below any longer. One day, a single plant seed wanders into one of the sky cities, and the children Kui, Hiruma, and Root discover it. Unable to resist the temptation to look into the world outside, they decide to undertake an adventure to the outside world, unknowing that once they set foot on the ground, they will never be able to return.

A girl moves from the city and goes to school in the country due to some circumstances in her father's job. Her new schoolmates keep her at a distance. There is a boy she'd like to get to know better, but she worries about how he might treat her and doesn't try to get closer. She begins to hate life in the countryside and longs to return to the city, but she ends up meeting a real god of wind.