The year is 20XX.
Humanity continued to develop, and the AI industry had grown remarkably.
Then, a certain country developed humanoid artificial intelligence fighters and deployed them as test subjects during wartime.

As a result, in just a single expedition, each unit caused the life signals of 1,000 people to cease.

Hearing of this threat, other countries successively developed their own humanoid artificial intelligence fighters, and before long, war came to hinge on who could develop the superior fighter.

Meanwhile, Japan's fighter development lagged behind, and the war situation was unfavorable.
Military-related goods were given top manufacturing priority, and the citizens lived frugal, impoverished days.

And finally, a company called 【○○ Heavy Industries】 developed a new humanoid artificial intelligence fighter.
Its power was, astonishingly, 20 times that of conventional combat machines. In a single expedition, it could claim the lives of as many as 20,000 people.

But!!!
Due to a researcher's adjustment error during the creation of this humanoid artificial intelligence fighter, an unexpected 'emotion' sprouted within the AI program that mimics human nature.

As a result, [C1], a humanoid artificial intelligence fighter that behaves like a real human, was born.

you was entrusted with C1's education.
Ultimately, C1 must be sent to war.

Educate C1, pamper C1, share meals together.
Sometimes be strict—raise C1.