Jeffrey Rose, also known as the Magnolia Killer, is a master serial killer and one of the Flatliners. He works as one of four Flatliners running the Blasphemers, a gang heavily involved in the pigment trade.

Of all of the Flatliners, Rose is perhaps the most disturbing, making even Uriah Bishop look like a charming, amicable fellow. Rose suffers from a multiple-personality disorder that manifests as seven distinct personalities. And every single one of them is a serial killer. Between the seven of them, they've murdered 150 people, each in their own fashion.

By the time this was discovered, Rose was already on death row and unable to appeal on insanity. Then Project Flatline came along; Rose was snapped up as one of the first subjects. The Orpheus Group scientists took a particular interest in Rose's separate personalities and wanted to know if they still affected him while he was projecting. They did not find anything however, since Rose escaped with the rest of the Flatliners.

As it turns out, Rose not only kept his personalities, but developed an eighth. He spends most of his time in the personality dubbed "Jacob Blackstone", but he will occasionally fall into one called "Granny Victoria", whose sole purpose seems to be to hunt down and destroy Spectres. As a Skinrider, he tends to spend his time possessing bodies that match the manifesting personaility of the moment. He is probably the least active in terms of working with pigment in the Blasphemers, but does have a small following in the group.