[quote=Rin]
Hmmm, if you need help with a backstory... Maybe he's an exile? He seems a bit less... Vicious than most fishmen, for one thing, so maybe they thought he was too soft and kicked him out?Just a random idea, I guess.
[/quote]

I wouldn't call the Fishmen 'vicious'. They're no more vicious then the other races. Although if the only Fishmen you've seen so far are the Arlong Pirates, then I can understand your misunderstanding