Some find this video disrespectful while others find it humorous - however Tristan Thompson's kiss of sideline reporter Allie Clifton (who he erroneously calls "Tina") is included here because it is very illustrative of several nonverbal signals.
Here we see the Cleveland Cavaliers power forward with his mouth configured in what is known as a "Loose Forward Lip Purse." This is significant for either clandestine disagreement or, as is exemplified here - clandestine plans. This is the moment he is deciding to kiss Ms. Clifton.
Moreover, those who make a forward lip purse believe they are a relative alpha to those with whom they're interacting/thinking about - AND they also believe they have a high probability of executing their plan successfully. It is important to differentiate this from other similar body language/facial expressions such as a "Tight Forward Lip Purse" or a "Lateral Lip Purse".
Here we see a low grade, social fear face - sometimes called a social etiquette fear face. It occurs during moments of embarrassment (although certainly there are many other nonverbals for this emotion). In this setting as well as with other subtypes of lower levels of fear - we see the mouth corners pulled backwards - but not as far and with much less downwards vectoring of either lip compared with high levels of fear. In the initial seconds of dramatic fear, the upper lip covers the upper teeth as it is pulled down and as the lower lip pulls down as well - exposing the bottom teeth.
This image also shows the tightening of Thompson's neck muscles - the dynamics of which are best appreciated by viewing the video above.
The fact that Thompson's eyes are turned toward the camera during the kiss tells us where he is placing his priority - with being a showboat, not with Ms. Clifton.
Additionally, the fact that his eyes are open during a kiss betrays that he is in a moment of low affection.
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