How do they all know each other? It’s apparent that Tom and Jon are friends, but what about Jenny? What type of train is it? Where are they going?

LoA

I wanted to dive into the story, and didn’t have time to explain everything. Jenny happened to be sitting in the compartment next to Jon and Tom, and every time the train stopped, she asked opened her door and asked if it was their stop (they were all going to a small town in an undecided European country). After this was repeated many times, Jon not so kindly told her to leave them alone, at which point she locked her door.

The train is pretty old fashioned. I don’t know much about trains, but this is an old one.