A mouth where, even at rest or during a state of neutral emotion, it appears to be smiling.

The corners of the mouth always seem to be at least slightly higher than the mid-line ("equator") of the lips like you're either partially smiling/smirking or are ABOUT to smile/smirk...

A lot of times this condition is accompanied by dimples...
Gina Carano appears to have a case of happy mouth. It makes sense since she is one of the best fighters in the world and one of the hottest fighters in the world. Palabra.
by Dark Overlord March 3, 2012
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