Knock knock. Who's there? Taco.

Taco who? Taco 'bout a good time!

Knock knock. Who's there? Pane

Pane who? I'm glass you're excited to meet me, but I'm a little transparent about my feelings.

Knock knock. Who's there? Existential Crisis.

Existential Crisis who? I'm not really sure, because the concept of identity and self is fleeting and meaningless in an infinite universe.

Knock knock. Who's there? Silence.