Post Description

Takes place in the same world as Muv-Luv Unlimited, where aliens called BETA (an acronym for "Beings of the Extra Terrestrial origin which is Adversary of human race") have invaded and mankind fights back against the alien aggressors with giant robots called Senjutsuhokousentouki (戦術歩行戦闘機, "tactical walking fighter jets"), usually referred to as simply Senjutsuki (戦術機) or TSFs, as almost all conventional weapons before simply didn't work.
 
The BETA first arrived on Earth in 1973 (in China and Canada) after arriving on the Moon in 1967 and being spotted on Mars in 1958. By 2001, the world population is down to 1 billion people, and most of Europe and central Asia have been wiped out. The Soviet Union, though, is still around, operating out of Alaska. When the BETA first arrived to Japan in 1998, 36 million people died within a week.
 
As history in the Unlimited world is different, there are many minor differences between the worlds in addition to the larger ones. For example, most of the slang words that Takeru use (like "maji" and "anma") are incomprehensible to the inhabitants of the Unlimited world (they end up calling it "白銀語/Shirogane-speak").