Buffy & Spike in a barn

I'm sorry that this isn't much to go on, but I'm hoping someone remembers this as it's driving me crazy...

Buffy & Spike are sent on a trip. I believe Anya & Giles sent them to either deliver something from the magic box to a client, or to collect an order. It required someone with super-strength/someone worthy/someone with knowledge of the people/creatures

They end up in a barn and I think the 'people' they are there to see are creatures that are part horse (this part may be wrong)

At some point in the barn, Buffy & Spike hide upstairs and they can hear the people/creatures below them. They're hiding, but they decide to get a bit frisky and that's when the people/creatures realise they're there, and Buffy and Spike end up fighting them.

Anyone?

Damn, I can't remember the name of it but I can remember a little more of the story.

I think buffy eats some sugar cubes and gets high or something. This causes her to insult the horse demons and that's why they attacked, i think...

Shelley
Sounds like "Dirty Back Roads" by the Deadly Hook. Her web page is Just Stake Me!

YES YES YES!

Guest #1 - that is also in the fic

Guest #2 - that is the fic I was looking for

*happy dance* THANK YOU :D