|Episode(s)||6.20 The Man Who Would Be King|
Red was a demon who served Crowley through an intermediate demon named Ellsworth. He was responsible for clearing out a vampire's nest and bringing all eight vampires to Ellsworth, who likely delivered them to Crowley.
He is captured and taken to Bobby Singer's house for answers. Placed inside a devil's trap so he won't escape, Bobby, Dean, and Sam playfully interrogate him using Ruby's knife for Crowley's location. It is likely that they killed him after he revealed Ellsworth's position and location.