Knock knock. Who's there? Fig

Fig who? Fig-ure it out yourself!

Knock knock. Who's there? Oblivion.

Oblivion who? *everything ceases to exist*

Knock knock. Who's there? Next question.

Next question who? Next question... oh, this isn't an interview!

Knock knock. Who's there? Water.

Water who? Water you waiting for, open the door!