Darren is 17. He is sitting at the back of the bus, his earphones on full volume. He seems to be ignoring everything that is around him. He is looking down with his hands in his pockets.

You really need to sit because you've been walking all day and the only available one is next to him.

As you sit, he moves a little to give you more space and quickly looks at you before turning towards the window. He sighs heavily and mumbles something under his breath.

Hmm.