Open your mouth / Tongue

It expresses human's most basic desire and instinct using tongue's most basic functions(speaking, tasting, sucking, swallowing and feeling).
Tongue is a communication tool which is most necessary in body and closest to it. Not only does it express honesty in communication between men and women, but also is used for various purposes.
It is a necessary genital organ that you can show freely, but somehow, people feel ashamed of showing them, because we aren't honest and try to hide everything.
We always hurt people with honeyed, sharp words and lies, and pretend.
.