Klaxo Sapiens
Klaxo Sapiens are the ancient civilisation in Darling in the FranXX that created the Klaxosaurs. The Klaxosaurs function as Earth’s immune system against VIRM; FranXX units are bio-mechanical weapons built from Klaxosaur remains and share this lineage, which explains the intimate Pistil–Stamen synchronisation required to pilot them. Zero Two is a human–Klaxosaur hybrid tied to this mythology.