Ben

Ben is a bodyguard working at Kerpolis. Since he's a banshee he can sense people close to death and that's how he choses his clients : powerful or illegale people who will pay a lot to stay alive. 

Ben actually lives in the Sidh or what he calls "under the surface ". It's an underground dimension which used to be a place for the deads. Ironically, the Sidh is now dying, collapsing on itself. Ben still refuse to leave.