He was there every day at the same time in exactly the same spot - had been for years. Thomas called him the dinosaur man.

In five-year-old logic this made perfect sense. Ever since he learned to talk Thomas had called trains dinosaurs - something about the roaring, the aggression, the clamorous speed of them had drawn parallels in his toddler’s brain and the association had stuck.

And this guy was here for the dinosaurs, no doubt about it.

Anyway, I remember the first day Thomas saw him. It was his first day at school and we were walking together over the railway bridge. He was there as always in his green plastic windcheater with his thermos and notepad, staring avidly over the bridge. You just think of these people as weirdo don’t you, without ever really wondering why, don’t you? So I steered Thomas away from him without even thinking about it.

But Thomas was fascinated.

“Mummy, what’s he doing?”

“He’s looking at the trains. Some people like to see all the different kinds of trains there are.”

“Do you think he knows they’re dinosaurs?”

But before I could answer, Thomas was off, tugging at his sleeve. The Dinosaur man looked surprised, but not displeased. I saw him smile at something Thomas was saying. He was probably harmless enough, but you can’t be too careful these days, so I stayed close.

Other parents hurried past, shifting their kids away from him and shooting us judgemental glances. Miserable sods, I remember thinking. Maybe because of that I went over to join them. Thomas was chatting away and for the first time ever the dinosaur man was smiling.

From that day we always left for school a few minutes early, so that Thomas could say hello to the dinosaur man. The dinosaur man had even showed Thomas his notepad and the long list of numbers. He was having a tough time settling into school and making friends. The encounters were what made Thomas eager to leave the house and go to school.

One Friday morning, Thomas carefully pocketed his notebook (he had his own now) and we set off in the drizzle. Dinosaur man waved and Picked Thomas up so he could see over the side of the bridge as a train whizzed by when three teenage lads sauntered past with their hands in their underwear and stinking of weed.

One of them had a fresh tattoo of something smothered in clingfilm and bloody cotton wool. I saw him eyeing up Thomas and Dinosaur man.

It was a small thing, a throwaway comment.

“Paedo,” he smirked. Then disappeared with his mates.

A barely audible piece of meaningless viciousness, but it was enough.

Dinosaur man was white. He carefully put Thomas on the floor and stepped back, looking at me with horrified eyes. I smiled and tried to reassure him, but the emotions chased their way across his face one by one, panic, disgust, fear. He didn’t know what to do with himself.

Thomas was chatting away, oblivious, waved goodbye to his friend and trotted happily off to school.

The next morning the dinosaur man wasn’t on the bridge and we never found out what had happened to him. I had never even asked his real name.