The weird thing that is whenever I come out the cat that was "talking" would look at me and run off. Including my girl who when "caught" would reow and run up and rub against my legs.
Have I uncovered a big secret?!?
Anyone else experience this
It's typical cat behaviour. Cats are far more communicative and intelligent than most people credit. Look around - at least one of them was smart enough to get into your house and into your Heart.
They are plotting your demise!
I've wondered what's communicated between house cats and strays they see through the windows. I imagine strays taunt the housecats, like kids taunting other kids for being momma's boys.
"What's the matter, you gonna come out of your cozy and warm human house and fight me? Oh that's right -- you can't! You're stuck in there! Haha!"
Owner calls out from inside the house: "Mr. Snookums, dinner's ready! Your favorite, turkey and giblets!"
Stray to other stray: "Did you hear that? 'Mr. Snookums'! Ahahaha! We're gonna go hunt us some rodents, enjoy your canned meat puree, Snookums!"
I agree with Plan, that the feral cats might be taunting your cat through the window (it actually does happen). Does your cat seem disturbed after these incidents? Some indoor cats get distressed with seeing cats outdoors, they feel their territory is being invaded. Additionally, is your cat spayed? Cats can smell potential mates, so if the cat outside is a male, something like that might be going on. I've even heard of whole males trying to mate with spayed females! I'd like to refer you to this YouTube video (read the video description), where something similar is happening with rabbits (I know they're different than cats, but they have a similar mating drive):