Hallan Aerf was a highly accomplished doctor that graduated from Singsong, well known for the generous help he often gave for little to no pay. He moved to Friedport, where he started up a clinic. His clinic was raided by the Patrollers once, after which he sold it off.

A trial was brought against Hallan Aerf by the Patrollers after a series of murders were traced to him, and he was publicly hanged.
Secrets ahead!
While anyone is free to read what’s ahead, everything else in this article is privileged knowledge only known to a few specific people in the world of Vendrith. Take particular caution to not assume your character knows these things, or avoid it entirely if you’re worried about keeping your own and your characters’ knowledge separate!
The Hallan Aerf that was hanged by the Patrollers was really just a body constructed from various animals and Monsters, with his head seemingly stitched on.
The secret half-brother of General Architrave, Hallan was really Hallan Aerf Architrave. He was trusted enough by the General that, when he seemed to realise he was going to be punished for his crimes, he entrusted Operation Blackout to his brother to oversee. Unfortunately for him, the plan would really end up being co-opted by Auldwell Fareawel, and then by The Scurvymaster.