Cats: WTF?

So, we're hosting our friend's cat for a week, and it leads me to pose some questions to all of my feline readers: Why you guys all enemies? I mean, what my cat ever done to this new cat, or the new cat to my cat? Nothing! But as soon as they lay eyes on each other, they're enemies.

They each are now stuck on two floors of the apartment, since each one is unwilling to try to pass the other on the flight of steps between them.

Unfortunately, both litter boxes are on the bottom floor. We'll see how that works out!