A good-hearted and affectionate vampire and the complete opposite of his older brother, Damon Salvatore. Later in the series, Stefan reverts to hisold ways as a Ripper to save Damon from a werewolf bite. His role becomes more antagonistic, after being forced to turn his humanity off. Eventually,he returns to his good-hearted and caring self and reconciles with Elena, but the relationship doesn't last long
During the years following his transition, despite the help from close friend Lexi Branson, Stefan has constantly battled with his bloodlust, and during the 1900's after "falling off the wagon" due to Damon's unhealthy influence, he widely became known as the Ripper of Monterey due to his inability to control his blood thirst. For a brief time, Stefan was romantically involved with the Original, Rebekah Mikaelson, and shared a close friendship with her brother, Niklaus. After many years away, Stefan returned to his hometown of Mystic Falls to visit his distant nephew, Zach. Stefan then saw Elena Gilbert for the first time while rescuing her after her parents' car drove off Wickery Bridge. After finding her personal records and observing her from afar, Stefan determined that Elena was definitely not Katherine. Still, he was strongly intrigued by her and decided to pose as a new transfer student at Mystic Falls High School to get to know her. They were instantly drawn to each other and they immediately bond, beginning a romantic relationship shortly afterwards. However, despite them becoming romantically involved, various and numerous obstacles begin to come between the two, making Stefan and Elena struggle and fight to be together. They grow distance after Elena's transition, and later break up, due to Elena's heightened feelings for Damon. He later discovered that this is due to the creation of a sire bond between Elena and Damon after Elena's transition to a vampire. He then embarked on a journey to Nova Scotia with Elena, Shane, Damon, Bonnie, Jeremy, and Rebekah to seek the the cure that can help break the sire bond. At the end of the fourth season, Stefan ends up heartbroken when the sire bond is broken and Elena still decided to choose Damon over him. Stefan decides to leave town and start over elsewhere. However, Stefan ends up being confronted by Silas, finally revealing his true form and locks him in a safe underwater. Throughout the fifth season, Stefan loses his memories due to Qetsiyah's attempt at incapacitating Silas and suffering effects due to Silas' confrontation, he slowly finds closure with Katherine as she helps him overcome his demons. Being a doppelgänger, Stefan's blood is used for a spell by The Travelers in order to resurrect their leader, Markos. During this time, he begins to grow close to Elena again and they are able to form a close friendship. As things begin to spiral out of control, Stefan was unexpectedly killed by Julian, a Traveler warlock, while trying to protect Caroline, but he was resurrected after Damon, Caroline and Elena's plan to bring him back from The Other Side is a success. However after Damon fails to return, he is left devastated at the loss of his brother as the Other Side collapses. Following this, Stefan moved away from Mystic Falls and had tried to start over and move on from the loss, pain and tragedy. Unfortunately for Stefan, he ended up being dragged back to Mystic Falls due to unexpected drama. During the eighth season, Stefan worked for Cade, the Devil. To keep both him and Damon out of Hell, he fliped his humanity switch off. While a ripper again, he attempted to murder Elena in her coffin, ripping out Enzo's heart, killing him as he was in his way. He then attacks Bonnie before going after Elena, only for Bonnie to use the Cure, taken from Elena's blood, on Stefan in revenge and self-defense. Stefan faints from being cured of his vampirism.