Klaxo Sapiens are humanoid alien species that were the previous inhabitants of Earth. 001 is the ruler and sole survivor of the Klaxo Sapiens.
Klaxo Sapiens appears as human but they have blue skin, hair, and eyes. In 001’s flashback of the last, several Klaxo Sapiens had horns and other alien characteristics. 001, as the klaxosaur princess, has horns, blue eye lines and eight spider-like appendages on her back.
Klaxo Sapien-VIRM War
The Klaxo Sapiens inhabited the Earth for millions of years, long before the human race came into existence. They were a highly intelligent race that specialized in advanced technology. According to 001, they were peaceful creatures who lived a harmonious lifestyle.
However, sixty million years before the main story takes place, the alien hive-mind species called VIRM suddenly invaded Earth and demanded that the Klaxo Sapiens surrender their bodies and souls to VIRM in exchange for eternal tranquillity. In reality, VIRM was looking to absorb their souls to enhance their lifespans and abilities. Naturally, the Klaxo Sapiens refused and thus war broke out between the two species.
Although VIRM was larger in size, the Klaxo Sapiens had the advantage due to their use of technology and evolution. As centuries of warfare dragged on, the Klaxo Sapiens built the Klaxosaurs with the use of male and female pairs; the female would merge with the Klaxosaur and become it’s ‘soul’ whereas the male would become the ‘core’ and maintain the control manuals.
Eventually, war and fighting replaced the peace and amiable lifestyle they once knew as the war progressed. The Klaxo Sapiens underwent an evolution as part of the necessity to survive but, in doing so, they lost their ability to procreate. At some point, they built two satellites on two rocks within Mars’ orbit, the Phobos and Deimos, which would open a warp gate, strongly hinting even the fighting with VIRM extended from the planet and into space.
When the war finally came to end with the VIRM being forced to retreat as the Klaxo Sapiens successfully fought them off, the planet and many cities were left in ruin, and the Klaxo Sapien population had drastically dwindled. Anticipating VIRM would return again, the remnants of the Klaxo Sapiens retreated into Earth’s core. The weaker Klaxo Sapiens dissolved into energy that the humans would later refer to as Magma Energy, while the stronger Klaxo Sapiens were equipped to pilot klaxosaurs for future battles.
War with Humanity
As centuries following the end of the war with VIRM passed, the Klaxo Sapiens peacefully lived in Earth’s core. However, by the twenty-first century, humanity discovered the usage of magma energy as a tool to increase civilization and technology.
The use of magma energy as a new all-encompassing and low-cost energy source by the humans caused an immediate and violent response from the Klaxo Sapiens. In 2037, the first Klaxosaur appeared and initially destroyed the magma energy factories before more confrontations with the klaxosaurs led to the destruction of cities and caused the human population to dwindle due to the casualties. According to APE, the war between humanity and the Klaxosaurs stretched for close to a century.
Initially, the humans were unaware of the existence of the Klaxo Sapiens and considered the Klaxosaurs as simply monsters. Only Dr. FRANXX and the APE council were aware of the Klaxo sapiens and kept this information hidden from the general population. According to Dr. FRANXX, the framework of the FRANXX units was inspired by one of the Klaxosaurs.By Episode 17, 001 is the last Klaxo Sapiens alive. Two members of APE asked 001 to surrender as they asserted she no longer stood a chance against humanity but she refused and they attempted to assassinate her. In retaliation, she killed them. Dr. FRANXX later tells Zero Two that 001 is the last of her kind and she is 001’s clone. 001 falls into a trap and is infected with a detonated virus set up by Papa, who is the head authority of APE and the leader of VIRM, but she sacrifices herself to give Zero Two and Hiro a chance to fight against VIRM and defend the planet. The return of VIRM ultimately results in the alliance of the Klaxosaurs and humanity in their joint desire to protect the Earth.
After a two year battle in space ends with the destruction of the VIRM home planet and the liberation of the souls held captive, the remnants of the Klaxosaurs returned to Earth, dove into the surface, and became part of the planet, restoring it.