I just read All Over It by NautiBitz and I'm hooked on the idea of Buffy having to sleep with Spike for some 'greater good'.

I'm after fics of any length, where for some reason (prophecy, demonic something-or-other, etc) Buffy and Spike have to sleep together. If there aren't many around, I'd be willing to compromise with something similar to KnifeEdge's Dust - i.e. where Buffy and Spike end up being thrown together to work and neither are happy about it to begin with - but then attraction builds.

TIA :)

Something In It by annapurna_2

Spike makes Buffy an offer she can't refuse. Set in Season 2, around the time of "What's My Line – Part 1." Then it...um...goes a bit AU.

I think there's one set in Season Four where Buffy has been poisoned and will die without sex. She nearly gives Giles a lap-dance before Spike is elected to help her out, if only I could remember the title. =s

In the vein of being forced to work together there's...

Not Your Ordinary Walk in the Park by Sandy

After Buffy enlists Spike's help in fighting a strange demon, it sends them to another dimension. There, Buffy discovers to her distress that she must rely upon Spike for her very survival. And then things get really interesting.

The one mentioned above about Buffy being poisoned-could it be "Bad Medicine" by Addie Logan?

In Heat by NautiBitz.It's here on SR.

Of course! Thanks, Guest.

Bad Medicine by Addie Logan

Buffy's sick, and only Spike has the cure. But is she in for more than she bargained for? (Season 4, slight AU)

Tricky propositions by Spikes_slayer08

Summary: Set beginning of season 5 slightly AU, No Glory or Dawn.

Buffy and the gang come into contact with a prophecy that will change their lives
forever. When Buffy finds herself faced with an impossible decision, she
finds herself with the task of propositioning an unlikely alli.
Will Buffy be able to do what must be done to save the world? Will she be
able to save her relationship with Riley? After everything is said and done, will she even want to?

I can't post links but it is here on SR, also at EF and FFN. Good read WIP but the writer is still updating.

Persephone by botias. It's on livejournal.

Take Heart by dutchbuffy2305
I liked Spikes evil point of view.