Not much is known about the life of this rugaru. All that is known is that this man completed his transition into a rugaru and then died. This rugaru's soul then went to Purgatory due to being a monster.
While in Purgatory, Benny Lafitte and Dean captured and interrogated this rugaru who knew where Castiel was. After much threatening, Dean managed to get him to spill the location. Dean then killed the rugaru with the demon-killing knife by stabbing it through the chin which impaled the creature's brain.