Kai came from a small group of betta fish people near the Philippines. His parents had already been mutated, it was higher up into their bloodline, passing to mutations down to him. These people were often hunted down, mounted on walls and bragged about since they were so rare.

Kai was young child when the area he and his parents lived in got found out by some divers, his parents got killed and taken away by these humans, and they tried to kill him as well, he had a fishing spear stabbed into his abdomen and taken onto the boat. One of the fishers though realized he was a child, still just barely holding on for life at that point. That one fisher decided to take him back instead of killing him like the rest.

Playing into the original use and purpose for breeding betta fish (proper name is 'Siamese Fighting Fish') he was used in battle again other, by the humans words 'abominations'. These were either other mutated fish people, creatues, or sometimes just regular animals to see who'd win.

It was used mostly for betting, seeing if he'd win or not against these creatures, due to this he had to learn to fight at a very young age, leaving several lasting scars on him, he'd been close to death several times but he somehow still survived. He had to kill several other creatures for his own survival, a night doesn't go by that he doesn't regret his actions.

It got to the point where he'd rather die than have to fight, refusing to fight back, leaving the duel to end early, it was boring to watch such a pitiful creature go down without a fight the humans thought. He even made an attempt on his own life after one of his battles, changing his mind last second, he wasn't sure wether he wanted to live or die but he didn't want to die in that horrible place.

After enough times of this the humans thought it'd be better to kill him off like they were supposed to do when he was first found, he overheard this deciding it was now or never to attempt his new escape plan, he had tried before but it was always unsuccessful.

This escape attempt was successful though, picking the lock for the cuffs he was in and leaving through an unlocked window in the middle of the night. He managed to escape, going far, far away from the place he was held most of his life. He then met Nex, Nox and Medina at this point. Those three were all friends already at this point when they found him, he would of course he terrified. The only places he's ever known is the water from when he was young, and the fighting rink from beyond that point.

He wasn't allowed outside at all, the real land and world was completely unknown to him, he was rightfully terrified of everyone and everything. Kai was one of if not the only person Nex kept around from that little group of friends after he lost his vision, Kai is incredibly helpful and caring, he's felt enough emotional distress to understand how it feels, thinking of what he would want if he was in his situation and offering that sort of affection and care for him.

Kai constantly helps Nexster with anything he needs, being sure to protect him from anything that could harm him. Kai gets scared whenever he can't find Nex or is by himself for longer periods of time.