The victim told investigators she was sexually assaulted by Josh Benson back in 2011, when she was 17 years old.
Charges from this latest case against Benson were filed Friday morning in juvenile court.
This brings to six the number of teenage girls Benson allegedly assaulted sexually while he was a juvenile.
He was charged Thursday with two more sex assaults prosecutors say he committed as an adult.
The total number of accusers now stands at 8.
Police said extensive media coverage prompted the eighth victim to come forward. They believe there may still be more victims out there.
Benson, of the 2100 block of Brown Avenue, was previously in custody for the sexual assault of five teenage girls while he was a juvenile.
"If you add mandatories up, if the cases are all heard in adult court, mandatories on top of mandatories - it's extremely serious," said Benson's attorney, Robert Mancini. Investigators say Benson met some of the victims in school and others through dating websites. He would befriend them, police say, and the victims would agree to sex.
However, when the encounter began, police say Benson would become physically violent and refuse to stop when the victims asked.
In fact, police say Benson would become 'more violent' when told to stop.
"It appears the more they asked him to stop, the more aggressive he became," said Bensalem Police Sgt. Andrew Aninsman.
Benson was a student at Bensalem High School for six months in early 2011.
He was then in and out of the district taking cyber school classes until last October.
His last posting on Facebook was back in August where he complained about being on house arrest.
In 2011, he also refers to having just gotten out of boot camp.
Benson moved to the area from Utah with his mother about three years ago.
Benson was arraigned on Thursday morning and sent to Bucks County Prison in lieu of 10% of $5 million bail. He was then transferred from Edison Juvenile holding facility to Bucks County Prison.
Bensalem Police are asking any victims who have not reported an alleged assault from Benson to please contact Det. Chris McMullin or Det. Dave Nieves Jr at 215-633-3719.
