From PRIMUS Database
As far as the Lion Twins know, Ignatius Zhou turned up on their metaphorical doorsteps challenging Atroxia to a duel. Atroxia wasn't one to turn down such a thing, and fought with her double until she won.
Nobody is sure why Ludwig called his foster daughter such a masculine name. Perhaps he was wishing for a son when he stalked Atroxia for her DNA?
After several attempted arrests by Atroxia, Ignatius had enough of her and tried to unleash a biohazard bomb. It didn't work. However, she got into her father's lab and made copies of herself.
Later still, Atroxia finally figured out where Ignatius came from thanks to Ludwig's attempts to replace the mayor with comatose vegetables.