Reason number one not to housesit UNLESS you're being paid:

Evil, robotic cats

Sure, you figure it sounds like all fun and dancing at first, as this image would seem to suggest:

Cute? Well, not when the reality is more like this:

It began with a joke from Stacy - the cat included in the house package meows constantly, and when it doesn't sound like a furry outboard motor, it's going for distance: meows that last ten, fifteen, twenty seconds. She initially called it robotic because she assumed its voicebox had gotten stuck, or perhaps there was something wrong with its programming.
Not so funny, now. It should also be noted that it has the devil's eyes, which would make sense as they're actually cameras.
The cat eats like a steamroller (seriously, one of the fattest felines I've ever seen); still meows nonstop, even with constant attention; and has somehow, despite, or perhaps as an extension to, its programming, it has developed a taste for human flesh. When I go over to feed and water and clean and whatnot, it's taken to pouncing on my calves and digging in, trying to extract the juicy bits of manflesh its owners apparently don't let it have. I wondered about the poor students in my biology class, and now I wonder if they became nothing more than kitty cookies for the deranged killer robot my professor deigns to call a housepet.

Next time: REVENGE OF THE POTTED PLANTS