Valentines day 2018, travelling home with girlfriend from Exeter to Exmouth. Boarded the train at 6:20. Train arrives into Exeter Central train station and approximately 30 university students board completely filling the carriages. I assume they were going to this event: http://www.exeter.ac.uk/news/events/details/index.php?event=7864

Shortly after departing the train they all start "singing" at the top of their voices various sport chants. The banging you can hear is them beating the ceiling with their hands and stomping on the floor. It was quite unpleasant and my girlfriend had a raging headache and started crying.
Honestly we didn't feel safe, quite a few of them had cans of beer and were clearly drunk. The train guard did absolutely nothing to stop this and I don't blame them, what is one train guard against 30 drunken lads?

After approximately 10 minutes of this the crowd disembarked at Digby & Sowton train station.

I tweeted this to GWR and they merely apologised and said to call the transport police if I felt threatened.