A sign of pleasure every human who has walked the world knows on a basic, primal instinct. Something that can break the language barrier and let those who are otherwise alien towards one another come to a common ground and enjoy one another's company.
When such a familiar trait is broken down from its initial intended form, unfamiliarity is born. With this unknown, mystery is brewed - and with the unsure comes caution, fear, panic, despair, uncertainty. That feeling of confusion laced with hesitance is what can really send a person to the breaking point. To that point in one's life where they want to leave. They want to leave, and run, as fast as they can, away from whatever it is that takes them from their own feeling of safety.
Music by Thief Fanmix: Nowhere, Midnight Whispered by Name