In the year 2025, a comet striking Earth triggers the arrival of alien invaders.
To fight against this sudden onslaught, humanity develops anti-alien weapons known as Androids. But despite their efforts, mankind is ultimately driven to extinction…

Time passes. In a ruined world devoid of humans, an android named Richt lives in solitude.
One day, a high school girl from the past, Seina, accidentally slips through time and ends up before him. Together, they embark on a journey.

By defeating aliens, Richt gains incredible strength through leveling up. As the two travel, their bond deepens, and they struggle to avert humanity’s extinction.

But then Seina is confronted with a painful truth:If the future is changed, Richt himself may disappear.

A science-fantasy tale of two souls weaving destiny across time!