I think that my favorite Power Couple™ from the later trilogy has to be Fareed and Seth. The idea of them alone, of this really ancient, 6000+ years old vampire falling in love with this madman scientist who wants to use science to study vampires, who wants (and does!) to revolutionize their world…

I just think their dynamic is amazing. It actually surprises me that, nine years later, I still have to see a single fanart or fanfic focusing on them