Christian Campbell was a hunter and the third cousin to Mary Winchester related side of the Winchester family. It is revealed that he has been possessed by a demon for quite some time and because his neck was snapped whilst trying to capture the Alpha Vampire, it is likely he is dead but still possessed by the demon. He is later released from his possession state after Dean Winchester stabbed him from behind while torturing Meg killing both him and the demon. He is portrayed Corin Nemec.
6.01 Exile On Main St.
When Dean was attacked by a djinn, his brother Sam came to rescue him already returned from Hell for a year or so and is hunting with the Campbell cousins Gwen Campbell, Christian Campbell, Mark Campbell, and their grandfather Samuel Campbell. The Campbells go back to the house Dean is sharing with Lisa and Ben to stop the djinn. Dean suggests they need to leave so the djinn could attack and they left. During the attack, Christian helps Samuel traps the female djinn Brigitta and loads her into their van.
6.02 Two and A Half Men
Christian is at the compound with the rest of the Samuel family when Sam and Dean brought a baby shapeshifter to their base. According to Samuel, Christian and his wife Arlene had always trying for a baby. Christian agrees to take in and raise the baby shapeshifter over Dean complaint that he shouldn't be raising anyone. 6.07 Family Matters Dean doesn't fully trust Samuel but when he tries to break into Samuel's office. Christian waylays him and they trade insults and threats. Christian attempts to discourage Dean from coming on the mission with him by mentioning his wife and quotes "Accidents happens", but Dean ignores his threats and investigates the mission anyway. Dean observes the Campbell family capture the Alpha Vampire and loads him into their truck. Sam confesses to Dean that the Campbell family are capturing some creatures for the sake of interrogation, and Dean resolves by following them to where Samuel is holding the Alpha Vampire captive. Dean and Sam manages to talk to the Alpha Vampire but are eventually discovered by Christian and the other members of the Campbell Family. When the Alpha Vampire escaped and snaps Christian neck,but when the Winchester brothers are distracted by the Alpha Christian rose from the dead and comes up and inject it with dead man's blood. Christian eyes goes black and several demons shows up and vanish with the Alpha. Crowley reveals that Christian had been possessed by a demon for a long time and serving his mole and that Samuel had been working for him too though tried to deny it. 6.10 Caged Heat The demon is now working at Crowley's side in a disused dark prison where he and amongst a cortre of high ranking demons are torturing and interrogating any and all creatures the Winchesters bring to them for information on Purguatory. He encounters Meg a demon still loyal to Lucifer (Satan himself) trespassing a dark corridor and incapacitates her with ease. Christian has her strapped naked to a torture table and begins slicing her Virgina with Ruby's knife sadistically demanding to know "everything". She is unimpressed by his methods and states that her vessel seen the worst treatment to which Christian smiles and escalates the torture more dramatically. Meg suddenly changed her screams and crying of pain to laughs of joy and comedy and when Christian questions her, Meg tells him that "Dean Winchester is right behind you...Meat Sack". At that moment Dean quickly swap Ruby's knife from Christian and stabs him from behind, killing him.