What is a good comeback?

Question

Whenever I'm thinking or even spacing out, I have a pretty blank expression on my face, but everyone is always commenting on how I look really sad.

I've had adults (mostly teachers even if I didn't know them) tell me "Smile" or "What's with the frown?"

Even this one guy at work was like "Why do you look so sad?" When I just walked passed him.

It happens all the time and all I can ever say is "I don't know" or feebly put on a smile and mumble "okay."

My question is, what is a good comeback when someone asks me "Why do you look said?" I'm looking for something funny or smart to say back.

So let me have em.

btw: They usually know I'm not actually sad, but they inquire why I look it.

Answer 1

Listen to Naruto Shippuden - Heros comeback

Answer 2

When they say 'you look sad' you say "thank you for noticing. I am praticing my sad look for after I get married. I just wanted to get it out of the way." Say it with a straight face. Then smile and walk on. And you're welcome.  8~)