Fish is best friends with Worm. He's insane and lacks quite a bit of common sense. Fish is calm and confident, and the latest scientific research has revealed that he does indeed have a brain.
Worm is an inventor at heart.
He always seems to find himself dragged into strange situations, but he's smart enough to avoid calamities most of the time. Nobody knows why he wears his hat all the time, but nobody really cares to ask, either. Josh tries to act average, and succeeds. He aspires to be a professional worm. That's about all he has for future plans.