JKSManga
I believe that the vampire assassin was sent recently by Jim Eno in order to sew discontent in the earth forces as well as increase the amount of damage that the Dalkie could reap.
So, who planted the vampire, and how long had it been. That Dillon fellow is probabky quite dead. And since this vampire knew lf the 13 families, but not Leo, i think its safe to assume hes been off the vampire world for a while. So did Jim find him and recruit him? Or someone else? Good luck on the Interview JKS
So it must of been one of the Vampire spy from a while ago, as they didn't recognise Leo from Quinns Vampire family, but I wonder if they are actually working with Jim/Arthur now. Hopefully with all 3 Leaders of the Human race fighting the Dalki will realise that they shouldn't underestimate the human race but Quinn and his people need to be careful