Diesel 31120

31120 is a diesel that appeared in the last illustration of "Fire Escape" buffering up to Gordon's train while. His headcode is "1X01", which is odd, as the "X" indicates "Royal Train or out-of-gauge load".

Also 31120 did not speak, it appears that he seems to have some respect for the steam engines. 31120 looks similar to a Class 37 diesel, the same type as D7101/Bear.