Feral Cat Aggressive to Only 1 Person

I live alone and adopted a male feral cat about two years ago.

The cat's behavior is fine among me and most of my visitors -- friends, parents, etc.

However, he is quite aggressive and hostile to one of my female friends. He hisses and actually growls when she visits me. She has a dog, but even when she comes without the dog, my cat acts up. She is the only recipient of this bad behavior.

Any ideas on why this is happening and how to solve this problem?

Thanks.

Maybe he doesn't like her soap, or perfume, or hairspray, and maybe the dog smell is a lot more obvious to him than to you, or he's just made that association.

Maybe something about her reminds him of someone who mistreated him in the past... Poor thing, he must be frightened.

I suppose you're already confining him to another part of the house/apartment when your friend visits?

I agree that it is likely the scent of the dog that leads to the cat's aggression. The easiest solution is to put the cat in a room while your friend visits.