feline face-off

So I'm sitting here eating my dinner, watching my daily dose of "Murder, She Wrote", windows wide open to enjoy the spring air. Opaw is up on the windowsill as she usually is when it's open, and suddenly I realize that I'm hearing something strange. Hissing? I've only heard Opaw hiss a few times, particularly at the vet. But she really was hissing and her tail was poofed out and she was trembling. So I go over to the window, and this is what I see:



Man, was she pissed. I guess that's not her friend. As you might be able to see, this cat did not appear to be wanting for food, and I don't think he was a feral cat. I leaned up to the window and this cat came right up, put his paws right under the window, and sort of silent meowed at me. I didn't know what to do! He didn't look like he was in need of care or food, but he also seemed sort of pitiful. After a short while he retreated a few feet from the window and just hung out there looking at me and Opaw for a long time. Now I feel bad, though, maybe I should have given him something to eat, but I was afraid he'd never leave if I did, and Opaw would disown me. But he was awfully cute, with his white mittens and his black chin. If he comes back and meows at me, I might be a goner...