Soukou no Strain  

s-strain, Strain: Strategic Armored Infantry, Мерцающий Стрэйн, 주광의 스트레인, 奏光のストレイン, 奏光的strain

In the distant future, humanity is divided into two factions known as Union and Deague. They have been at war with each other for so long that no one remembers when it all began. The primary weapon system of the Union military is the manned weapons platform Strain, while Deague uses an unmanned version called Tumoru.Sara Werec, a 16-year-old girl from a respected family, attends Grapera Space Armed Soldier Academy in the Cranial Solar System, where she trains to become a full-fledged Reasoner (a Strain pilot). Her brother, Ralph Werec, was sent on a mission 130 light-years away when Sara was just 11 years old. This journey takes 400 years of objective time to traverse by even the fastest Union spacecraft but only two subjective years (time as experienced by those within the spacecraft) due to the theory of relativity. Despite losing their parents at a young age, the bond between Sara and Ralph is very close, and it's her deepest desire to be reunited with him. One day, Sara's planet is attacked by Deague forces. To her surprise, she discovers that her brother, Ralph, was one of the kidnappers who captured a mysterious girl sleeping in a capsule. In order to find out the truth, Sara gets into a Strain and chases after him. However, she is ambushed by Ralph, and the Mimic, a copy of the pilot's brain that controls the Strain, is damaged.