Humans often miss what we are telling them. They don't understand our body language. Indeed, they often just don't even see it.
Many of us have humans that just don't understand us.
This is the shoulder lick, which we all do when we are feeling a bit uneasy, or a bit fearful, or we want to calm ourselves down a little. It's a quick turn to the shoulder, and a quick lick on the fur.
It's like the "phew" noise that humans make when they are getting to the end of something stressful.
It's quick. So quick that humans usually miss it. They just don't understand what we are saying. So quick that it only takes about five seconds or even less.
If you have a really good human pet, they will learn about the quick shoulder lick. They will begin to notice it. And they will be on the way to understanding you.