In the near future, spirits and monsters are in full sight. A boy leads a group of people with special abilities as they plot against a massive organization that takes advantage of a certain incident and eventually know the truth about their world in the process.

In the Four Islands Archipelago, people can use Grav-Shoes to fly around! This is the story of Asuka Kurashina, a transfer student that arrives at Kunahama Academy from outside the Four Islands. After seeing the ability of wearers to soar in the sky, she quickly develops an interest in flying with the Grav-Shoes and also joins the school’s FC (Flying Circus) club to further her passion.

In the aftermath of the most devastating conflict mankind had ever experienced, the tiny island of Shikotan became part of the Sakhalin Oblast… and on the unhealed border in this remote corner of the world, friendship among children from two different countries timidly blossomed, striving to overcome language barriers and the waves of history. Inspired by true events.