According to fanlore: Headcanon (or head canon, head-canon) is a fan's personal, idiosyncratic interpretation of canon, such as habits of a character, the backstory of a character, or the nature of relationships between characters. The term comes from the fact that it is the canon that exists in a fan's head.
Code: 0000 or Absolute ZERO is an Elite pararasite, having the 0000 rank he was overall the best FranXX pilot in his Squad. 0000 is even stronger and more skillfull than the profrained "Partner-Killer" or Zero Two. But during one of the sorties disaster struck his Squad and the plantation he was assigned. What shall a...