Mystery cough

So I begin with the mystery cough*clearing my throat and coughing out*
What exactly is the mystery cough? I do not have a detailed explanation because it is quite baffling. But a suitable definition would be something people do to make the other person uncomfortable. I'm painting different scenarios as they come to mind to show what I mean by mystery cough. Let's see if you can identify with them.

Scenario 1:
She is in the bus heading to her destination. She gives the bus conductor signal and then as she announces her bus-stop,another passenger starts coughing.Hey,the other passenger may naturally have cough but how come it is when she talked that the passenger probably intimidated by her, decided to respond with cough.

Scenario 2
Collecting ones change is now a problem.So in the market after purchasing the things on the list and it was time for payment.It was then and only then,the seller developed cough. Oh! She's having a sore throat and all of sudden ,it is when she hands out change to the buyer that she starts the cough.

Scenario 3
They were very much in love. The time came for him to introduce her to his family. It was when she appeared on the D-day that his family members developed cough especially when she had to introduce herself.

Scenario 4
Thankfully, he got to the interview venue on time beating the traffic. He tried to gather himself and prepare for the encounter. And then ,it was his turn and as he handed over his C.V to receptionist, it was then the receptionist started coughing.

Scenario 4
Walking down the street,she approached some group of guys who were lazying about. And then,as she passed the mystery cough was within her earshot.It came from the guys!

In the above scenarios,one thing was common-the mystery cough! It is used to taunt,annoy or make the other person feel uneasy.  As for me ,I do not let it bother me anymore. Normally I do react but I  have taken it to mean the instigator is sick and needs healing!