Series: (Dark and Evil Are) Not Synonymous
Genre: Crossover, Drama, Angst
Story Pairing: Hint of Giles/Ethan if you squint
Series Pairings: Xander/Spike, Giles/Ethan/Anyanka, Tara/Willow/Oz, Drusilla/Cordelia, Buffy/Riley, Angel(us)/Wes, Harry/Draco, possibly others
Rating: FRC (Fan Rated for Children)
You can find the story here: "Family"
and the rest of the series here: The "Not Synonymous" Universe