One day the main characters find a pest in their home or workplace. However, just as one of them is about to shoo it away or, if one of them isn't so merciful, exterminate it, an Obstructive Bureaucrat shows up telling them that the animal is endangered, and thus killing it or even evicting it would constitute a crime.

Now the characters have to deal with an annoying and troublesome pest that they just can't get rid of, or even possibly have to actively ensure its safety and well-being.