That one is a breeding female, the underbelly area is where she holds her eggs. Usually fisherman mark those lobsters in some way so they’re not fished up, since when they’re not carrying eggs it’s hard to tell whether they’re breeders or not. By keeping these in the sea, fisherman ensure there will be more lobsters to catch next season.

I think he’s dead. Dead lobsters spoil quickly, that’s why they’re supposed to be killed right before cooking or boiled alive.