Squirrel vs. Cat

I am not making this up!

I am sitting in our living room, and our cat A.J. was sitting on my lap snoozing. We have four floor-to-ceiling glass windows/door that look out onto our patio, and a squirrel came up to them and stood on his hind legs with his paws on our window. He moved from window to window... and then... and I promise I'm not making this up... I swear he knocked on the window.

Kitty snapped open her eyes and flew off my lap to the window. Next thing I knew, that squirrel flung himself against the window again and kitty did the same from the inside. This happened a couple of times, and then the squirrel took off.

A.J. obviously knew that that goofy squirrel was "knocking" on the window, and he must know that A.J. lives in here! I wonder how often that squirrel has been taunting poor A.J. from the outside???