Lou Bollo was a human living in an alternate Earth, where he was stunt coordinator of a television series called Supernatural, which narrated the life of Sam and Dean Winchester, but only as a narrative fiction.
Lou brags to an attractive young woman that he oversees all the stunts and coordinates all the fights for the show, and she points to Sam and Dean, who are in the midst of a fight with Virgil, and asks if the fight is one of his. He, two stunt doubles, and Kevin Parks run to put a stop to the fight, and in the confusion Virgil flees with the key from Sam's pocket.
Later, when Virgil appears on the set and kills both Eric Kripke and Bob Singer, Kevin hears the shots fired. He remarks to Lou that he didn't think they had gunfire scheduled that day just before Virgil enters the scene and shoots both Kevin and Lou.