It is unknown how Severen became a vampire but it is most likely to have been bitten either by Jesse Hooker or Diamondback ( other members of his vampire clan ), He is first seen dragging Caleb ( a cowboy bitten by his clanmate Mae ) to his mobile home to kill kim, but it is revealed by Mae that he has just been transformed, which causes Severen to become incredibly frustrated. As the days pass he is seen stealing a car to use it on another trip with his clanmates, burning the previous mobile home, seducing two girls to kill them by telling them that he will pay them some drinks and bullying Caleb along with Homer, a vampire kid. The then clan enters a bar where Severen starts harrassing a customer by spilling his drink, insulting him and spitting on his face but after the man tries to punch Severen, who grabs Caleb to block the punches, then Severen tells the man to continue punching Caleb and then he forces Caleb to hit the man back, he then kills a biker by snapping his neck and drinking his blood and on his most splendid performance he kills the bartender by slicing his throat with a spur kick, then the clan proceeds to burn down the bar. Because Caleb had left a boy he was supposed to kill escape, he went to the police and they raided the motel where they were staying causing a dangerous shootout for them because of the daylight but with the help of Caleb ( who is almost killed while making it to the vehicle on broad daylight ) they manage to escape which causes Severen to stop being hostile at Caleb, even giving him one of his spurs. After Caleb escapes with his dad and sister they start looking for them as the vampires ( with the exception of Mae ) want to kill him and Homer wants Sarah ( Caleb's sister ) to be his companion. Severen encounters Caleb later that night , while trying to kill Caleb he is runned over by a 18 wheeler but survives, though heavily injured, his strenght and speed are not affected by the injuries because of his vampiric condition. At the end he is killed when Caleb makes the 18 weeler explode, carbonizing him.
Severen is the most violent, aggressive, and sadistic member of the group. He never doubts on killing anyone, although it is seen that he cares about his partners, he also acts as an older brother towards Homer. From the beggining he displays an intense dislike towards Caleb and the fact that he was bitten by Mae makes him incredibly angry and frustrated as he doesn't wants him to join the group, despite this he tries to make caleb to become a cold blooded killer so he can join the clan but this is most likely only an attempt to help Mae to have Caleb as her companion rather than helping Caleb himself. Despite his sadisctic and deranged personality he can be seductive as seen by the way he lured two girls in order to drink their blood.