Shirogane Takeru found himself inexplicably transported to a world that resembled his own in many ways, with one major difference: For nearly 30 years, mankind has been at war with the alien BETA, who have succeeded at wiping out over half of humanity and had nearly captured the entire Eurasian continent. As Takeru tried to come to grips with this bizarre new reality, he realized too late that the majority of humanity will be abandoned with the Earth, as the chosen few escape to the stars, hoping to find sanctuary.

Now, equally inexplicable reasons, he finds himself returned to the first day of his time in this alternate world. Will the experiences and knowledge he has gained allow him to make a difference?
Well, if Mitsurugi is right, 
and he does end up contributing,
،إن كانت ميتسوروغي محقة في مساهمته
Mitsurugi hat recht. Wenn er am Ende
einen Beitrag leistet,
Si Mitsurugi está en lo cierto
y acaba contribuyendo,
Si Mitsurugi está en lo cierto
y acaba contribuyendo,
Comme le dit Mitsurugi, si cela améliore
les performances de l’escouade,
Beh, se Mitsurugi ha ragione
e lui darà il suo contributo,
Como a Mitsurugi disse,
se ele contribuir com o esquadrão,
Мицуруги права.