I'm thinking that too. I don't know how old he/she is. The reason for the pot bellie is she was very starved and is slowly putting on weight.. still skinny though.
I'm going to try putting him in a lee's betta keeper next to an aggressive male (Sid Vicious) and see how he reacts..
If he is a male that's gonna be bad news :( it would mean I couldn't get the king betta I've been dying to get. I would have to get rid of one of my other males if I was going to keep Annabel Lee and still get the king. On the bright side it would mean I could get another female possibly.
If he turns out to be a boy I'm naming him General Lee.