shin jiho, known as xero, lives on his own in a tiny house in the fire nation. his mother passed away while giving birth to him, and his father died of some unknown illness when jiho was seventeen. he has no siblings or any other family he knows of. he was trained by his dad, who was really strict and didn't give jiho any love of affection whatsoever. instead, he gave him the knowledge that his son didn't need or want. xero tried to oppose, but his father was determined and unbreakable, as if he knew he was going to die and didn't want his skills to waste. soon he started using violence, both emotional and physical, against his son, as a way of both teaching and child-rearing. this resulted in jiho being constantly terrified. he tried spending as much time outside as possible. his father didn't seem to care, as he was always too busy. xero always went to woods, played around, trained. after some time, he almost lived there, feeding on small animals he managed to roast with his powers. he grew up to be an independent loner and decided, that he will never, ever be like his father. he will never hurt even a fly, so he was genuinely nice to every single person he met. this changed after his dad's death, though.

the heads of the fire nation saw the tallent and potential in him, and decided he will make a perfect soldier. he strongly refused as it was against the only rule he set for himself. the battle wasn't easy, but eventually he menaged to convince them using his charms. that's when he started doing it on a regular basis - at first involuntarily, then for fun. he also became a sort of a rebel, a troublemaker, when he realised he was so loved that all of his offences were overlooked. he started causing more and more trouble, sometimes even 'accidentally' uncovering some dirty little secrets that made him hate the nation even more. if the war was even going to take place, he plans a betrayal, but he doesn't talk about it with anyone.

he might seem perfect for the countless people who love him,but under the facade he's just a scared, lost child with a traumatic past, who deals with his pain by showering everyone with affection, a bit over exaggeratedly and not really genuinely anymore, and also by passive-aggressively destroying his nation, which he believes is the main cause of the evil in his world, hence should be eliminated.