Scylla was a cannibal.
Personally, she enjoyed her meat slightly undercooked, so she could get the moisture just right, and her spices were also milder than usual.
She also didn't like her food preserves prior to being served, which meant every time she was hungry… someone had to die.
There was no preserving her meal afterwards.
Scylla had friends who shared in her twisted hobbies and enjoyed the same delicacy as her, so she turned her disgusting practice into a business.
She would procure, process, and even sometimes cook the meals that her comrades would enjoy, and they would give her money or small favors in exchange.
Of course, these people readily agreed.
They were too high-profile to risk their names being marred by murder or some kind of illegal activity. Also, since most of them weren't particularly deep into the criminal Underworld of the Alliance, they didn't know how to properly go about killing and processing humans.