Someone who pointlessly knocks on the door.
When it'sa Jar-Jar.
A kiwi!
Because freedom rings
Knock, knock, knockin on Heavens door
A visit from the university board of ethics.
Technically, just two, but it is really hard to get them to breed in captivity.
Nobody asks, 'who's there ' when you try and tell a knock knock joke.
Because they don't like random people knocking on their doors
They don't believe in a higher power.
Someone who shows up to your door for no reason.
