You’re not friends. You’ll never be friends. You’ll be in love ‘til it kills you both. You’ll fight, and you’ll shag, and you’ll hate each other ‘til it makes you quiver, but you’ll never be friends. Real love isn’t brains, children. It’s blood. It’s blood screaming inside you to work its will. I may be love’s bitch, but at least I’m man enough to admit it.
Spike to Buffy and Angel, Buffy the Vampire Slayer: Lover’s Walk