Aika-chan no Chikyuu

Aika Tsubota, a twelve-year-old girl, writes a manga about the environment and its importance for the future of the planet. She dies shortly after completing her work, and her parents publish it in her memory.

The story, titled "Secrets of the World," is adapted into a single OVA sponsored by a charity dedicated to fighting ocean pollution. The anime follows the themes of the original manga, highlighting the beauty of nature and the urgent need to protect it from human destruction.