He was anxious. Worried and stressed. Didn't want to show his real self. Couldn't even if he wanted to anyway.
In his world weakness is unforgettable.
No mercy for unlucky souls who show emotions. Because emotions are for  weak and weakness is something you stay away from.
  
It is not a choice. It is a must. First rule of survival. Your game face. Straight, blank, practiced but natural.

The problem was he didn't fit any part of this segregated society. He knew that.

To start with he was an outsider, an Immigrant, foreigner, an alien he would have been called if he was in USA.

How race, colour, age, sex did not matter. Once you have the accent in London you are the one. The one who arrived late.

Any accent would do. North London, south London, Essex, Brummie, Scottish, Irish, Indian, Patois but not immigrant one.

You get stamped straight away. Everybody knows that you are new here.
They treat newbies different in London. No matter where are you from or who you engage with, you get looked down.

Anybody who was born in the UK will judge you right there and then. Mostly you start the interaction with minus points.

You get struggle in the beginning but get used to it in time and accept it sometime very soon.
Once the peace made with unavoidable faith you start playing the game.

Learning the rules. Rules that emposed in to you by unwritten society rules. Everybody knows but nobody speaks of.