Draco/Harry, NC-17 for violence and sex, (pseudo)-bestiality
I've never read a werewolf story this rich, this lucidly violent, this credible. Calanthe's concept of the weakwolf that is Draco's between-form, possessing him between man and wolf, had me gasping. The complete absence of dialogue is a wonderful technique for this story.
I located it on hp_roughside, which is members-locked; if anyone knows of an unlocked location for it, let me know and I'll change the link.