This next story set during Season 2 begins after Passion and goes AU. It's written with such skill that it takes you down the rabbit hole. Seriously. As told through Buffy's POV in the second person, this Buffy/Angelus fic manages to be the most believable presentation of the pairing I've ever read. This story is subtle and enthralling.
For anyone intrigued by the Buffy/Angelus pairing or simply would like to see a prime example of excellent writing, I present to you: