Spike watches her with barely conceived envy as she sips her Diet Coke on ice. It's not often that he finds himself longing for human comforts, but summertime in California tricks him into thinking he's thirsty. Watching Buffy drink in front of him makes a mockery of his death, and watching her swallow makes his teeth hungry to pierce her neck and drink her. That would wipe the smirk off her face.
Buffy notices his frustration and feigns ignorance. This does not improve his mood. Then she leans her head down and dips her tongue into the glass, quick and furtive and so damned skilled. It makes him all too aware of how dry his mouth is and how much he hungers for the sweet crimson life that courses through the Slayer's veins.
She grins at him, the ice glittering between her teeth, and shatters it.
Then he drags her to the ground, and she just laughs at his ferocity. He hates the sound, and he hates her, and he loves her. He kisses her fiercely and her tongue is freezing in his cold, dead mouth, but improbably, there's a fire starting between his legs. He kisses her, he fondles her, and then he fucks her. And he knows that she knows how much he wants to kill her.
And he knows that she laughs because he never will.