I am fast coming to the conclusion that the story behind Jason and Evander (reincarnations of Jerry and Eric) is basically a gangster scenario, with magic added in.
Modern world, magic is just another factor in life. High powered magic users can get into high ranking positions in society, which is what Monet Merritt has gained (partially because somehow she regained her higher dimensional powers early in life), becoming known as the High Sorceress of her city.
The problem is, certain figures in the criminal world did not like her active attempts to quash the use of magic by organised crime, and set about to control her by kidnapping her kid brother Evander, and tricking him into a geas-bound service. Evander was then trained as an assassin for the biggest crime boss of the town, Fallorrini, often being sent to take out people who worked for his sister.
Somehow Jason Barton gets involved in underworld dealings. He gets annoyed at the crime lords and decides to take the fight to them.
At one point, he talks to Monet, asking her why she does nothing about the crime lords of the city. She admits that her hands are tied because of her brother's enslavement to Fallorrini, and also reveals that whatever is powering the geas holding Evander is something from a higher race - one higher than her, since she has tried and failed to break the geas.
Jason, having instantly recognised who Monet is due to his own past life memories, swears he will do anything and everything he can - even if it includes calling in Tael - to free Evander. Frankly, Jason wants Eric back, and Evander is this life's incarnation of Eric.
As it is, a showdown where Fallorrini brought his pet assassin in to take Jason out ends up with Fallorrini losing said assassin due to the power source fuelling the geas not being able to stand up against Riftfire - which Jason has no clue what the hell it is, but it works anyway.
Jason gets away with Evander, taking him back to his apartment and keeping him there, partly for his protection, but mostly to unblock his past-life memories and subsequently seduce him.