Jeffrey Brevard started out with a small-time band that was going no where. His band could only get gigs in small bars, where Gertude Hall was frequently following the band. Jeffrey was extremely depressed over this. He was in a small-town Floridian with big dreams of taking over the musical world by storm. He was a terrible student who largely got by on his looks. Jeffrey would form Acid Washed, a decidedly retro hair metal band, intended to evoke the halcyon days of rock'n roll. But due to the band's uninspired musicianship and terrible song lyrics, his band booked only the few small shots in three years. However, despite this unpopularity. The band would meet a mysterious benefactor who introduced them to a dark power.
This benefactor would be Elvis of all people, he offered the group a bargain. To sacrifice virgins and they would gain success. The virgins would be used to impregnate and help reproduce Nef creatures. He however would make a big mistake, by helping abduct Cassie Hack and leaving Vlad back on earth. While Cassie and Georgia were trying to find out where they were, Vlad was bewildered at what happened. While Vlad wished to confront Six, he soon understood he couldn't because he was still a virgin. And virgins were apparently vulnerable to Six's attacks.
As the day went on, Vlad would soon meet up with Gertude and the two soon had sex. As morning came, he explained that Six had Cassie and their new friend Georgia. With Gertude's help they used an apparent fan to get themselves in and Vlad immediately attacked Six and his band mates. While he did get some scratches, Six realized he could no longer hurt with his demonic magic. Elsewhere, Cassie was able to fight back when Elvis was about sacrifice her and Georgia, Elvis was killed by the entity of the Nef world when Cassie shoved him in her place.
Almost immediately after which, Vlad is able to get Six to open the portal to the Nef world and save Cassie and Georgia. Gertude, deciding to get her own personal revenge flashed Six quickly. Then quickly taking his guitar, stating she hated his songs and kicked him apparently into his own version of Hell. Gertude kept his guitar and mounted it as a memento.
However, this defeat was only temporary. Six would reappear in Hack/Slash: The Series #21 Mind Killer. Ashley Guthrie, who still had plans to kill Cassie Hack, decided to partner with him to settle accounts with her. But first to get Six out, they needed his guitar which Gertude still had. So to lure all them, Ashely used the little power he had left in dreams. He spooked Vlad by having him fight many characters and diary products, Cassie began to recall weird dreams, and both made Gertude believe she needed to present the guitar to them if she was to prove herself as a loyal fan and finally be loved by music (musicians in this case).
While Cassie and Vlad, quickly caught on that it was Ashley behind their dreams. She, Vlad, and Georgia(whom was traveling with them) decided they had to destroy Six's guitar. Gertude was not so willing to believe, the three women began to argue and fight over it. Though Vlad was able to break-up the cat-fight, there was little time to actually get to the guitar as the police would soon surround all of them. Six and Ashely had the group where they wanted them, all the had to do was get the guitar. Ashley had just the means to get the guitar through the apparent psychic Muffy Joworski, who's husband was also a decorated police veteran of the police station.
Ashley possessed her body and took complete control, killing an officer and crashed the police car right through the station. He killed many officers and eventually found the guitar and freed Six, who was now an orange color. However, before they could exact revenge on Cassie, they soon realized Six didn't come back alone. Six had inadvertently brought back bizarre tentacle creatures who took hold of the dead bodies, Ashely had killed. Taking almost anyone living, the creatures showed many their worst fears. Only Six, Ashley, and Muffy's husband, were not yet being tortured. While Six quickly freed himself, before he could fight, the creature that was tormenting Cassie got one of its tentacles into his left eye as he entered the Nef world.
As he did he quickly saw the horrors and hell that Cassie's own mind had gone through; her father's death, killing her mother twice, the slashers, and the fear of killing Georgia. He does eventually get the creature off, but it apparently has either taken out or damaged his left eye. After he does, he uses the Nef world to have his powers recharged, however its not without a price. His masters (the entity) wants payment, Cassie Hack. He returns to free his fellow hostages, however Ashley still bloodthirsty wants to finish what they started. Six tries to explain he has to take Cassie, Ashley behaves childishly.
Six sees there's no cooperating with him and knocks him out. As he leaves with Ashely (in Muffy's body), he explains he sold his soul to the devil. While Cassie knows he also came for her, Cassie states she's not afraid of death. Still remembering what he had seen in Cassie's mind, Six mercifully leaves her and states he has to trade him as payment for his newly restored powers. While Cassie doesn't want Muffy to be taken along with them, Six explains she's been dead since Ashley took control of her and leaves.
However, this doesn't seem to be the end for Six Sixx. As he's later seen (with an eye-patch over his left eye) holding auditions for a new would-be-singer named Rachel, but what he has planned for her is not yet known.