Love Like Blood, near the end of Chapter 5:

There was indeed a spark between us, and we both had accepted it for what it was. She was the vampire, I was the mortal. She could kill; I could keep her from it. There was a balance between us that no one could take away; we'd both promised each other's safety.

We’d never promised anything else. We didn’t have to.


I like how that one ended up. :)