Naj had a happy early life with her three parents and her baby sister, but everything changed with the big catastrophe of Atlantis happened. There was a big villain attack that called for the help of both surface and Atlantic heroes. In the end, the heroes were victorious but the cost was tremendous, besides the massive collateral damage, there too many deaths to count... But little Naj could count three of these deaths, her parents.
The great mourning that happened wasn't enough to abate her need for revenge and that was her undoing. Naj ran away to hunt down who killed her parents and by doing so, it was so easy for her to slip through the cracks. The system was too overwhelmed by all the rebuilding and relief work being done that if not for Lupi, the little sister she had forgotten about, who then would remember her in the all the little ways a toddler could.
Who got her was Man O' War who then sold her to another person... She never got the names, not even to the other ones she would soon be fighting to almost death, sometimes past it.
It soon turned good at it.
Maybe too good, because soon its opponents turned harder and harder, to other kids, to adults, to beasts... The damages its body was reaching a limit it couldn't sustains anymore and so it did a fatal mistake that costed its arm... But also gave back its freedom back. She doesn't remember much of what happened, just that it woke outside in a random trench. She was soon found by people who turned it to the authorities, where it finally was reunited with Lupi... She was so big, Naj vowed to never leave her being again.
But trauma never leaves its preys so easily, her anger and attacks were difficult to control, making difficult interact with others and work properly. So her new Guardians, the same as Lupi, gave her an option, to participate in this test program that would chose youngs like it to go to the surface and try their hero academy, Lupi would come with her if she accepted, plus there would be financial help... It accepted.