Buffy a Sit

I read a story here a long time ago where buffy was A Sit and spike was a caged vampire used for training them

I know the one you mean, Alice, but naturally I can't remember the title. Sorry.

I'm commenting so that when somebody with a better memory comes up with the answer, I'll find out too.

I think this may be the one you are looking for

The Rose by coalitiongirl [NC-17]
Summary: The Watchers Academy- where young potential slayers and watchers go to train in demonology, magic, and combat so that they can someday fight vampires, demons, and the forces of evil. There are evil magic professors, a principal with a secret, and an unbreachable wall between the slayers and the watchers. And in the basement, imprisoned vampires scheme and dream of destroying them all...

http://dark-solace.org/elysian/viewstory.php?sid=3006

Well, that's certainly the one which I had in mind, Melly.

Thank you so much!