Aquacat
Aquacat already has thousands of leagues full of fish, why would he want to join your Justice League? How many fish does it have?
Aquacat’s got it made. What, you have some problem you need Aquacat’s help with? Well I can’t hear you because I’m a thousand leagues under the sea in fish paradise. Whatever it is I’m sure Supercat will take care of it. And if not, well, I don’t really care! I live in the ocean with all the fish!