This unnamed man worked as a traitor to the resistance in Apocalypse World.
As part of a plot by the angels, the man told Arthur Ketch and Charlie Bradbury of a supposed angel kill squad out to kill some resistance prisoners. As planned, Arthur and Charlie attempted to ambush the squad, but were captured by them instead for torture for information on the resistance.
After the Winchesters are informed of the capture of their friends, they dug into how it happened and learned of the man who informed the two of the kill squad. The man was brought in front of the Winchesters, Bobby Singer and Castiel. Though the man claimed not to know what was happening, the others didn't believe him. When pushed about tipping Arthur and Charlie off about the kill squad, the man admitted to having told them about but claimed not to have set them up. In response, Dean had Castiel use his powers to inflict great mental pain on the man before he stopped on Dean's signal. Dean then asked the man again and he eventually admitted the truth and gave up the location where the angels were holding Arthur and Charlie.
Following his exposure as a traitor, it is unknown what the resistance did with the man, if they executed him or left him behind during the following exodus.