Not with a bang, but a whimper.
She expected their first time to be hard and angry, with bites and scratches acting as kisses and caresses. She expected Faith to push into her space, punching and yelling and all sexy bravado, until one of them snapped. She expected a crypt wall digging into her back and Faith's teeth digging in anywhere she could reach.
She didn't expect a pleading glance, a whisper, and a ghost of a touch across her cheek. She didn't expect Faith to melt into her, her body supple and conforming in an extended moment of holding back a flood of want and need. She didn't expect a bed, soft and inviting, sinking beneath them as they fell onto it together.
And when Faith finally kissed her, she moved slow and held Buffy's gaze, affording her more than enough time to back away, to change her mind. She licked her lips, a quick, furtive flick of her tongue that made Buffy whimper, transfixed by the motion. In the moment before Faith's lips finally touched hers, Faith sighed gently and closed her eyes. That one short exhale said so much more than any words she might have tried. It said "finally" and "please" and "perfection" and all sorts of other sweet nothings that Faith would normally deny, but in that moment, Buffy felt the deluge of Faith's emotions. And she tried, with the curve of her lips, the way her mouth fell open, in the way she sank her fingers into the fine hair at the base of Faith's neck, to show her the same tenderness.
Everything in their past had built to this moment. They were magnetic, destined to repel or cling to each other, depending upon how they lined up the firestorm of slayer energy. They spent so much time, too much time, pushing against each other, sensing each other, feeling the pull at the outside edges of static pulse that kept them apart. All it took was a slight shift, a subtle realignment, and suddenly the need to touch, the explore, to give became impossible to ignore.
The moment their lips touched, Buffy forgot all the compelling reasons she'd resisted this inevitable moment. This, this perfect connection of lips and fingers and bodies and everything, this was worth living and dying for. It was a reason to save the world and keep saving it.
A lot.