A couple of years ago I adopted a stray cat,I called Mistopholes. She's pure black except for a white spot on her chest. Last week I came down stairs and thought I saw her in my wifes chair and she left in a black streak out the back door. I thought that's weird and closed the glass door. Poured myself some coffee and looked up and there was a black cat looking in. It was a lot smaller than Mistopholes and had no white spot???
Turns out it was a ~12 week old kitten that my wife had found sleeping in our garage and Wifey started feeding her. Now we have two black cats.
They don't seem to like each other, yet.