Well than, I'll leave it up to you. Karine is going to be tracking down a Blood Mage operating inside the city. You can either chose to be working for one of the nobles to kill Karine for some reason, or just about anyone else really. Either or, you might get into a fight with Karine anyways. If it's because you're going to assassinate her, well that's self-explanatory. But if you kill the Blood Mage, Karine is going to be pissed that you stole her kill. And she will demand satisfaction.