You are a fishmonger.
Fishmonger is just one of those words that you do not need to know exactly what it means to get the sense of it. It just sounds insulting. Fish being just the opposite of human, meaning-wise – and the sound of the word, no matter how much you like fish, sounding fishy. And MONGER?! My goodness. Maybe it’s because it comes close to MONSTER? Or just because, I don’t know, it sounds unpleasant, just the NG and the MONG and the GER all put together with FISH?
Even if no one ever told you what a monger was, you’d know you wouldn’t want to be called that – even if you WERE a fishmonger. I don’t imagine that a seller of fish is delighted to introduce himself at cocktail parties with, “How de do? I’m a fishmonger.” Even mongers of other goods don’t tend to use the monger bit. I guess I’ve heard of a cheese-monger but almost always in a sort of comical way or a self-consciously pretentious way. Because how else COULD you be a cheese-monger? It’s just a funny word! But it might be fun to have coffee mongers and cell phone mongers and haute coutre mongers and cocktail mongers and then send them all to that cocktail party to meet the fish and cheese mongers.