That's why you should never allow one of those alien creatures in your house. When I was very young, we had this marmalade cat. It was very nice and friendly and everything, but it kept secretly shitting behind sofas and fucked up the carpets. So the day came when we got rid of it. These people were coming around to pick it up and hopefully give it a good home. As their car turned into the drive, the weirdest thing happened. The cat walked into the downstairs toilet and stood up on the seat and neatly shat into it. We were astounded but it was too late for that cat and he was taken away.