Richard Sen is a frequent guest to NTS, appearing on various shows between 1 May 2016 and most recently on 1 October 2019. Richard Sen has been played on NTS over 30 times, featured on 36 episodes and was first played on 6 February 2014.

One of the UK's original graffiti taggers, Sen was notorious for leaving his 'Coma' tag all over the London Transport system in the 80s. Being from Wembley, he was partial to tagging the Metropolitan line ("his line") and was one of the first to paint an entire car top to bottom with a crew of 20. Sen has since become a successful DJ, is half of Padded Cell and runs the label Mixed Blood.