I've seen a lot of fics where Buffy is poisoned/cursed and doesn't wake up until Spike kisses her awake. 

How about instead, Spike is the one who's asleep?

The story must be set in season 5.

Spike falls under a sleeping curse that can only be broken if someone he truly loves romantically kisses him. The person doesn’t have to love him back.

There should be a revelation that if Spike couldn’t/didn’t love anyone then the curse would have killed him instantly, which stops Buffy from claiming that Spike can’t love.

Bonus points if Angel and/or Riley get hit by the curse and die. 

The gang should try and track down Drusilla in order for her to wake him up. If she shows up, then she tells them that Spike doesn’t love her in that way anymore and kisses him to prove it.

Somehow, the gang figuring out that Buffy needs to kiss Spike. Buffy kisses Spike to prove that he doesn’t love her – and he wakes up.

Willow or Tara could also get hit by the curse and one kisses the other awake.

Would be great if Dawn suggests that she or Joyce could kiss Spike awake before it’s revealed that it has to be someone who Spike loves romantically.

After the kiss, Buffy shouldn't immediately jump into a relationship with Spike.