Samuel William "Sam" Winchester is a Hunter as well as a Man of Letters, and along with his older brother Dean, is one of the main protagonists of Supernatural. Both Sam and Dean are related to the Winchester and Campbell families - a Letters family and a Hunting family respectively. The pair also share a bloodline with Cain and Abel. Because of this, Sam was pre-destined to be the True Vessel of Lucifer (whilst Dean was Michael's). Both Sam and Dean were raised in the hunting life by their father John after the demon Azazel killed their mother. Sam left the Hunting life to pursue a career in law, and most likely would have married his college sweetheart Jessica Moore, had she not died. When the series begins, Sam is reluctant to start Hunting again, but after Jessica is killed, he jumps back into the hunting life. However, he has repeatedly tried to back out of Hunting in the hope of finally having a normal life that he wanted. He also wants revenge, drinking demon blood until he successfully kills Lilith. Over time, Sam accepts the lifestyle, knowing this is his life now, and he refuses to do it without his brother. He repeatedly sacrifices himself for the greater good, highlighting his selfless nature. Sam is very mentally strong, evidenced by his ability to overpower possession by Lucifer. Sam also served as a vessel for the angel Gadreel before expelling him.