The otome game "Princes of the Galaxy," released in A.D. 2038.

A boy from the distant future, playing a game from 1700 years ago at his grandfather's house,

gradually became convinced of a connection between the game and reality.

If this were a typical rosy scenario, he might have spent his days laughing.

But it seems "hard mode" is currently active, and an interstellar war is about to erupt.

Knowing of a future where the capital planet faces annihilation, he enrolled in an officer academy to pilot a space fortress.