Paw of fury

So, the scariest thing that ever happens to me is when I'm in the bathroom with the door shut. Every time I'm in there, this mysterious and very dangerous thing happens. First, I hear the sound of metal clinking against the hardwood floor outside the door. Then I hear this very low scratching noise, like something very large is scrabbling around. Then it gets quiet for a few seconds, tick tick tick, and then suddenly, this massive black, fur-covered arm comes shooting out from under the door. Sometimes it's just a paw, and sometimes it is the whole arm, all the way up to the arm pit, and the paw has these huge claws coming out of it, and it waves around, and if I get brave and try to bite it, it swipes at me.
It is the most terrifying thing ever. I totally love it. Someday, I'm going to catch it. But not yet.