The term itself has developed to its current form gradually over the last three years. The phase was originally created after they witnessed someone soil themselves in the Ibizan hotel Es Calo Playa. The holidaymakers found this hilarious and they developed a traffic light system to judge the various stages of soiling. The individual who has fully soiled themselves was judged to have scored red and the term "redded it" had been born.
Obviously adults soiling themselves is a rare occaisson so the holidaymakers decided that they would class any soiling incidents as a "southern" e.g southern red, amber or green. Far more commonplace was witnessing adults making themselves sick through alcohol abuse and the "Northern Red" phrase was born. Over time the phrase has been abbreviated to "Northerned it".
Magma: Yeah I northerned it.
Pedro: Ah right, do you want a chuddy?