Somebody who no matter how hard they try and keep a
straight face while
looking in the mirror, are secretly laughing at
the funny lookin guy/girl looking back at him/her from the inside of the mirror.
Funny lookin guy/girl looking in the mirror- Today, you're gonna keep a
straight face for five minutes. Don't underestimate yourself,
what is that a smirk forming in the corners of your mouth? You want to keep your teeth? Yea, keep a
straight face on your face. If anybody messes with you, say what you just said, just like you just said it.