National Geographic has made a very interesting video on how easy it is for cute little sewer rats to swim into your toilet and make a surprise appearance while you are doing your thing.

The reason that rats can easily make it up your toilet is that as well as being great swimmers, they’re pretty flexible. This lets them easily navigate the twisting maze of plumbing in your house. Worst of all if you ever catch one in your toilet, flushing won’t help, the furry toilet monster will just be washed back into the sewers.