I prefer shutting the hell up rather than rant at the people whom I dislike, they'll just be happy when I rant at them knowing they pissed the hell out of me.
"It's better to remain silent and be thought a fool than open ones mouth and remove all doubt" - Mark Twain
It's a great pose, and you express a feeling of naughtiness and seriousness. To model, one must emote, and just being pretty allusion from the uneducated eye.
Love the shot!