Spike/Angel.
The characters are really hard to get right, and the relationship, especially between Spike and Angel is intensely complex but Romany has a good handle on their voices and writes them just the way I like it. Modern, I guess, not so much focused on the sire/childe thing, and not too much on the past so much as who the characters are now which is for me, the most interesting aspect of the pairing. How do Angel and Spike help themselves (and each other) get past al of the history and the baggage? The show’s writers didn’t focus on the angst, they made the two interact humourously exchanging quips and whatnot. And Romany stays true to that more than many other authors I’ve seen.