I'm hoping someone will recognize the story so here goes -

It's a one - shot set in Season 2 but after Innocence because Angelus is walking tall and doing his evil guy act like only he can.

Buffy's in the cemetery brooding over him and bumps into Spike who is mucho pissed because Dru is ignoring him now Angelus is back.

They get into an argument deciding the other is to blame for everything - He thinks she should have kept her legs shut while she blames it on him and Dru for coming to Sunnydale.

As usual the tension turns sexy as both come to the conclusion that they were made for each other. They have both kept their distance and use the fighting as a way to keep their feelings hidden knowing that if they acted on it then their fates would be sealed.

The minute they kiss everything else is flung out the window as both admit they belong to each other.

I'm pretty sure Angelus comes upon then havign sex but neither care as he or Drusilla mean nothign to them now.

Hopefully, I've given you enough so that someone knows it.