Buffy x Faith
Buffy first noticed something in that dark alley when Faith staked the vampire.
Faith first noticed when she felt the smaller slayer watching her in the same alley.
But neither of them knew what it was they were noticing.
Buffy felt protectiveness towards Faith when Kakistos showed up. One she had never felt for anyone before, including Angel.
Faith felt a desire to tell Buffy everything, a desire she couldn't understand.
Still neither slayer had figured out what they were feeling for each other.
Buffy didn't realise that she was more angry at Faith for not trusting her when Angel returned.
Faith wouldn't admit, not even to herself, that the only reason she attacked was because she was jealous.
Buffy didn't understand why Faith going over to the mayor hurt her so much.
Faith didn't get why, now she had the father she always wanted, she missed a certain blonde so much.
Neither girl realised what they felt for each other until, Buffy slid the knife into Faith. Then like a spark both girls knew at once, but by then it was too late.