Quinlan Vos was a Kiffar Jedi Master in the Jedi Order and a General in the Grand Army of the Republic during the Clone Wars. He hailed from the planet Kiffu in the Inner Rim Territories. With long, dreadlocked hair and a band of pale yellow across his upper face, Vos was gifted with psychometric powers which allowed him to "read memories" from inanimate objects through physical contact.
Vos had an ongoing struggle with the dark side of the Force, particularly after he sustained recurrent amnesia after he overdosed on an illegal drug administered by an enemy shortly after the Battle of Naboo. The Sith Lords Darth Sidious and Count Dooku both showed an interest in him.
Though Quinlan Vos was a good Jedi in many ways, he suffered an ongoing struggle with the dark side that continued long into the Clone Wars. He was consumed by hatred for his great aunt, Tinté Vos, after discovering that she had sacrificed his parents to Anzati vampires, and he eventually murdered her in cold blood, completing his fall to the dark side.
Having committed many evil acts during his time as Dooku's Dark Acolyte, Vos yet managed to convince his old friend Obi-Wan Kenobi that he still served the Republic, and he helped Kenobi escape from both Tol Skorr and Asajj Ventress. Vos was very mindful of his cover as a Dark Acolyte, sacrificing a childhood friend, Shylar, so that he wouldn't reveal his identity. Even so, Quinlan blew his cover by rescuing his great aunt, whom he shortly thereafter killed. Having waged long war with his inner demons, Vos displayed great strength of character by ultimately overcoming the dark side during the Clone Wars.
Against the strict mandate of his Order, Quinlan fell in love with Khaleen Hentz and at the end of the Clone Wars became her husband and the father of their child, Korto Vos. Quinlan also forged an intimate Force bond with Aayla Secura, who once said that he had been like a father to her. Vos had a rather sarcastic sense of humor. When he faced Tsyr and Bok on Kintan, for example, he said that the two of them against him—who was wounded at the time—was unfair, before asking if it would be easier for them if he closed his eyes. Quinlan was openly disdainful of clone troopers, who in turn disliked him, but he was loathed by Sergeant Kal Skirata. Despite this general mutual enmity, Vos was civil, if not friendly, towards Commander Cody.