Magnus’s RPG empire on the portal.

I pull out my crossbow and try to shoot her in the leg – "she's mine"...

She has already disappeared, and you are left without the book.
For completing the quest, you gain +1 level.
You exit the cave, but the quest giver has been destroyed, and a note from Biara is lying nearby; he knew a lot. We'll meet in Cranir. What are your actions? There is a portal to Cranir nearby.