During the World War, children were forced to evacuate their homes.
The land where they gathered and lived became known as "lagoons".
Many "lagoons" are self-sufficient and provide a humane, albeit humble, way of life.

Kai, a young mercenary boy, lives in a "lagoon" that is an abandoned amusement park.
During a joint operation with an adult-centered warlord called "The Army," Kai meets a girl,
Her name is Mio.
She has silver hair.
She is not a talker.
She is good at shooting.
And she is a girl who can't wear bandages.

Kai learns Mio's secret.
He reached out to Mio because he had some thought in his mind.

Mio starts living at Kai's house.
Kai's childhood friend, Doctor, is also with her.

No one knows yet where this encounter will lead.

[From Steam]