Someone who pointlessly knocks on the door.
Ali-luyah at last you've opened the door!
Just a moment, someone's knocking on the door..
She has no arms... Knock knock Who's there Not Suzy
To get to your house... Knock, knock. Who's there? The chicken.
A visit from the university board of ethics.
A melancholy.
Someone who shows up to your door for no reason.
I'll be goddamned.
An argument